CIP Journal Articles

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Effect of Vine Harvesting Frequency on Sweetpotato Root Yield Components and Gross Income in Southern Mozambique
(Journal Article, 2025-01-13) Munda, E.; Muassabo, R.; Francisco, E.; Da Gloria Samuel, C.
Sweetpotato is widely produced by smallholder farmers in Mozambique with average yield of 7.3 t/ha. One of the challenges in sweetpotato production system is inadequate seed during the rainy season resulting in low productivity. The few sweetpotato seed multipliers (Decentralized vine multipliers (DVMs)) resort to several vine harvesting frequency to meet farmers seed requirements at the peak of demand. Repeated vine harvesting contributes to sweetpotato root yield reduction. The objective of the study was to evaluate the effect of vine harvesting frequency on sweetpotato yield components. Three experiments were set up in three farmers’ fields in Vilankulos district inhambane province in Southern Mozambique in the 2021/2022 and 2022/2023 cropping seasons with a sweetpotato variety Esther. The experiments were set up in randomized complete block design with three replications in each farmer’s field. The treatments were no vine harvesting (control), harvesting only once at 8 weeks after planting (WAP), harvesting twice at 8 and 12 WAP, and harvesting three times at 8, 12, and 16WAP. Total storage root yield, number of roots per plant, root diameter, and root length were measured in each treatment. Results show that storage root yield was significantly higher in control (22.1 t/ha) and harvesting once (17.8 t/ha) compared to harvesting twice (11.8 t/ha) and three times (9 t/ha) (P < 0.05). Additional harvesting from one to two resulted in 33.7% yield decline. Vine harvesting twice resulted in 46.6% storage root yield decline compared to the control treatment. The same observation was noted for the number of roots per plant, where five roots per plant were observed both in no harvesting and harvesting once treatments. A 40% decline in the number of roots per plant was observed when vine harvesting frequency was increased from one to two. No treatment effect was observed on the root diameter. Increasing vine harvesting frequency from one to two or one to three resulted in a 14.7% income loss from sales of both vines and roots. Vine multipliers are recommended to harvest vines for use as planting material only once if they want to benefit from the roots for consumption or commercialization.
Adoption of Orange-Fleshed Sweetpotato (OFSP) technologies in Southern Ethiopia
(Journal Article, 2025-01-16) Tenaye, A.; Gebeyehu, S.; Cherinet, M.
Addressing malnutrition and vitamin A deficiency in Ethiopia necessitates innovative, food-based solutions such as biofortified crops. This study assesses the adoption rates of Orange-Fleshed Sweetpotato (OFSP) and examines the factors influencing adoption among project participants, non-participants, and counterfactual households in the former Southern Nations, Nationalities, and Peoples’ (SNNPs) region. Primary data were collected in 2023 through a survey of 990 households across six districts, and logistic regression was employed to identify key determinants of adoption. The findings reveal OFSP adoption rates of 53% among participants, 56% among non-participants, and 42% among counterfactual households, with significant variation across regions. Factors positively influencing adoption include household education, proximity to health centers and OFSP multiplication sites, frequent extension contact, and access to agricultural services. This study underscores the potential of newly released OFSP varieties to enhance food security and resilience in malnutrition-prone areas. The comparable adoption rates between participants and non-participants highlight significant spillover effects from long-term interventions, suggesting widespread community benefits. However, the limited adoption of complementary OFSP package components points to the need for enhanced training programs and streamlined technology dissemination strategies. These findings contribute to understanding how biofortified crops can be scaled effectively to improve food security and nutrition, offering valuable insights for policy and program design.
Developing commercial-scale fresh sweetpotato root storage in tropical areas of sub-Saharan Africa
(Journal Article, 2025-01-16) Stathers, T.; Otieno, B.; Kipkoech, B.; Rees, D.; Precoppe, M.; Muoki, P.; Low, Jan W.
As food systems across sub-Saharan Africa transform and urbanise, demand for all-year-round supplies for the raw materials is increasing. This demand can be met through combinations of staggering crop production, purchasing from diverse geographical areas, and storing produce. Focusing on the increasing use of orange-fleshed sweetpotato root puree in vitamin-A-rich food products, we ran a series of storage trials in Kenya to investigate whether commercial-scale fresh orange-fleshed sweetpotato storage could provide a stable supply of roots for puree production. The trials studied storage of roots of two sweetpotato varieties (Kabode and Vita), using washed versus unwashed roots in wooden crates, and mains grid power versus off-grid solar-powered storerooms for four-months. Following curing at 30 °C, roots were stored at 20–23 °C, and quality assessed. After four months storage, 54–59 % (Kabode) and 63–83 % (Vita) of initial root weight remained suitable for processing into puree. However, weevil and sprouting problems occurred. Vita outperformed Kabode for most criteria. Neither root washing nor different storerooms had a consistent effect on root quality. Subsequent trials in a solar-powered store investigated if lower temperatures of ≤15 °C and 90 % rh, with pre-harvest dehaulming could reduce weevil development, sprouting and rotting in stored roots. While control of sprouting and weevil damage was achieved and dehaulming improved stored root quality, while washing reduced it, high incidence of rotting and root weight loss occurred. Increasing store ventilation did not reduce rotting. We conclude that further trials with well controlled storage environments are required to understand how raw root quality, dehaulming, harvesting and handling practices, curing conditions, air exchange, and packaging materials affect quality during fresh root storage.
Spatiotemporal trends in Anopheles funestus breeding habitats
(Journal Article, 2025-01-11) Aduvukha, G.R.; Abdel-Rahman, E.M.; Mudereri, B.T.; Mutanga, O.; Odindi, J.; Tonnang, H.E.
Effective identification and control of malaria vector larval breeding habitats are crucial for the management and eradication of malaria. Despite its importance, the last decade has seen a decline in data availability and intervention efforts due to reduced attention and prioritization. This study addresses the geographic data scarcity concerning Anopheles funestus larval breeding habitats in a malaria-prone region of western Kenya. Employing a two-step methodological approach, we integrated multi-criteria decision analysis (MCDA) and rule-based fuzzy logic analysis to evaluate the spatiotemporal similarity or divergence of these habitats. The analysis spanned a five-year interval, 2008, 2013, and 2018 with 2013 serving as the base year for both hindcast and forecast predictions. The MCDA utilized categorical land use/land cover (LULC) and edaphic variables to identify potential breeding habitats, while climatic and topographic variables and spectral indices were analysed using fuzzy logic to assess the similarity or divergence of these habitats over time. Validation of the MCDA and fuzzy logic models was performed using a flight buffer distance based on adult An. funestus presence points (n = 136), supplemented by a limited number of larval breeding locations (n = 12) respectively. Our findings identified 147 potential An. funestus larval breeding habitats across the study area. The fuzzy logic analysis predicted a high degree of similarity (85.03%) in potential breeding habitats between the study years compared to the base year, with a divergence of 14.97%. This study demonstrates the feasibility of using semi-automated methods to detect both permanent and impermanent An. funestus breeding habitats under conditions of limited data. The methodologies developed provide a timely, cost-effective tool for enhanced surveillance and management of An funestus mosquito larval breeding, offering valuable insights for stakeholders involved in malaria vector monitoring and control.
Harvest index is a key trait for screening drought-tolerant potato genotypes (Solanum tuberosum)
(Journal Article, 2024-07-04) Lozano-Isla, F.; Farfan-Vignolo, E.R.; Gutierrez, R.; Blas, R.; Awais, K.
Drought stress is a significant constraint that affects the yield of almost all major crops. Its impact is expected to worsen due to global climate change and human population expansion. Potato (Solanum tuberosum L.) is the third most important food crop worldwide, but it is highly susceptible to drought stress. In order to understand the effects of drought stress on yield and identify traits for selecting drought-tolerant potato genotypes, we evaluated the response of a range of agronomic and physiological traits in 15 potato genotypes under well-watered (WW) and water deficit (WD) conditions. The harvest index (HI) was found to have a high plot-based heritability (0.98), indicating that it can be used for the indirect selection of drought-tolerant genotypes. In contrast, SPAD was sensitive to detecting early drought stress in potatoes. Drought-tolerant genotypes, including CIP392797.22 (UNICA), CIP397077.16, CIP398190.89, CIP398208.219, and CIP398208.620, were able to allocate limited water towards tuber production rather than biomass. These genotypes showed high tuber production under WW conditions and increased photosynthetic activity and water use efficiency under WD conditions.
Impact of farmer training on potato yield a case of smallholder potato farmers in Malawi
(Journal Article, 2024-12-19) Kangogo, E.; Otieno, David Jakinda; Okello, J.J.; Mwenye, O.; Kapalasa, E.
Due to rapid population growth, agri-food systems have been under increasing pressure to adapt and innovate to sustainably meet the growing demand for food. This requires advances in agricultural practices, technology and distribution networks. Farmer training has been proven to be a crucial component in this transformative process. Equipping farmers with the necessary knowledge and skills becomes paramount to optimize agricultural productivity while also improving their coping with the effects of climate change. This study applied the difference-in-difference method with inverse probability-weighted regression to analyze the impact of farmer training on potato yield. Results showed that 40% of farmers who received training interventions were members of farmer groups and had more farming experience compared to the control group. Additionally, the annual crop enterprise revenue for training participants was USD 255 compared to USD 134 for the control group. Results also showed that potato farmers who participated in positive selection training reported an increase in yield by 14%. On average, training participants were able to increase their potato yield by 1.33 tons per acre. These findings demonstrate the importance of providing targeted training and specific skills in order to enhance farm output. Furthermore, improving access to credit and supporting effective participation in farmer groups would increase farm yields.
Developing a Cryopreservation Protocol for Embryonic Axes of Six South American Peanut Genotypes (Arachis hypogaea L.) Using Desiccation–Vitrification.
(Journal Article, 2024-12-23) Tacán, M.; Andrango, R.; Tapia, C.; Sørensen, M.; Vollmer, R.; Pérez, C.
The present study investigates the cryopreservation of embryonic axes from the peanut genotype ECU-12466, demonstrating a successful protocol involving a 1 h desiccation on silica gel followed by a 1 h cryoprotection with Plant Vitrificatin Solution 2 (PVS2). The average dimensions of the excised embryonic axes were 5.6 mm in length and 3.5 mm in width, with plumule lengths averaging 2.2 mm. Notably, germination rates for cryopreserved axes ranged from 71.4% to 85.7%, showing resilience to varying desiccation and PVS2 treatment times, particularly at 1 h. Shoot length was significantly enhanced by a 1 h PVS2 exposure, while longer durations resulted in phytotoxic effects. Rooting rates were higher for samples treated with shorter desiccation periods, with 54% rooting achieved at 1 h of PVS2 exposure, contrasting sharply with just 16% at 2 h. The moisture content of the embryonic axes remained stable between 9.3% and 9.5%, indicating no detrimental impact from the applied treatments. To evaluate the protocol’s broader applicability, five additional peanut genotypes (ECU-11401, ECU-11418, ECU-11448, ECU-11469, and ECU-11494) were tested. While cryopreserved samples demonstrated high germination rates of up to 95.4% after 15 days, the rooting success was significantly lower (25.2%) compared to the control group’s 90.9%. Following transplantation, the growth performance varied among genotypes, with a success rate of 93% for ECU-11494. Overall, this study elucidates the critical parameters for optimizing cryopreservation protocols in peanut embryonic axes, contributing to more effective long-term conservation strategies.
Foliar Zn Application Increases Zn Content in Biofortified Potato
(Journal Article, 2024-12-30) Zevallos, S.; Salas, E.; Gutierrez, P.; Burgos, G.; Boeck, B. de; Mendes, T.; Campos, H.; Lindqvist-Kreuze, H.
Given the widespread micronutrient deficiencies in vulnerable populations, crop biofortification has been proposed as a solution to increase nutrient concentrations. This study aimed to determine the effect of combining biofortification strategies on the agronomic characteristics and nutritional composition of potato. The effect of foliar fertilization (FF) with zinc (Zn) on five potato genotypes (G): four biofortified clones developed through conventional breeding with different Zn levels (high, medium, and low in Zn, and one high in Fe and Zn) and a commercial variety (‘Yungay’) were evaluated. At harvest, the number of tubers per plant, the weight of tubers per plant, and the average tuber weight were evaluated as yield components, and tuber samples were collected for micronutrient determination. For yield components, the analysis with linear mixed models showed no significant G × D interaction effects, but highly significant differences were observed among G. The Zn concentration in tubers showed a highly significant effect in the G × D interaction. The simple effects analysis showed that biofortified genotypes responded to FF with Zn by significantly increasing the tuber Zn concentrations by an average of 43% (range 28–61%), despite growing in alkaline soils. In contrast, the ‘Yungay’ variety showed a 6% increase. Clones biofortified through conventional genetic improvement responded better to agronomic FF with Zn compared to the non-biofortified commercial variety, demonstrating that both are synergistic strategies that can achieve a significant increase in Zn concentrations in tubers. The result of this study might be used to further biofortification efforts and decrease nutritional deficiencies.
Gender analysis is not only about gender: reshaping the potato breeding priorities to increase varietal adoption in Kenya
(Journal Article, 2024-12-06) Friedmann, M.; Polar, Vivian; Mendes, T.
Public breeding programs are pushing to implement demand-led breeding to increase variety adoption, while tackling multiple challenges for increased production under climate change. This has included the improvement of variety target product profiles involving multiple stakeholders. A special case involves the unexpected and rapid spread of the Shangi potato variety in Kenya. This variety was not an especially outstanding variety and the levels of its traits did not exceed the expected thresholds defined in the target product profile for table potato in East Africa. By examining the customer segments looking at gender but also social contexts of smallholder and disadvantaged farmers such as access to markets, inputs, and labor, it became apparent that ready availability of potatoes for consumption, processing, or planting was of prime importance. Given the storage and market constraints, Shangi's very short dormancy, which had been assumed to be a negative trait for farmers, women cottage processors and consumers, was actually meeting the needs for available product and planting material. Consequently, this provided these groups increased control over their productive activities. The case study presented here analyzes different components of potato variety change in Kenya. It explores the challenges and tradeoffs faced by public sector breeding programs and how gender analysis from a broader inclusion perspective can uncover the underlying causes of varietal adoption. Focusing on the Shangi potato variety, the case study reveals a series of lessons learned that have re-shaped the definition of breeding priorities.
Potato production under zero tillage with rice straw mulching as a promissory technology to diversify rice-based systems in Southwest Coastal Bangladesh
(Journal Article, 2025-03) Ramírez, D.; Hossain, M.M.; Rahaman, E.H.M.S.; Mestanza, C.; Rinza, J.; Ninanya, J.; Kreuze, Jan F.; Mendiburu, F. de; Loayza, H.; Gatto, M.
Extreme precipitations that promote flooding, salinity, and soils with low drainage and aeration are challenges that affect food production in the Southwest of Bangladesh. After rice cultivation, most lands are kept fallow, emphasizing the urgency of research on techniques that allow crop diversification to guarantee food security. In this study, 2 years-trials on farmers' plots were established in 3 locations of Khulna district-Bangladesh to test potato cultivation under zero tillage with rice straw mulching (ZT) in comparison to conventional cultivation (CT) after rice. A soil quality index (SQI) using the partial least squares method was run considering key soil indicators related to crop production. ZT allowed a higher tuber yield and a lower C footprint than CT. Although neither method significantly affected soil organic carbon stock, there was a significant increment from season 1 to 2 (29.0 ± 11.3 and 45.8 ± 9.4 Mg ha−1, respectively). ZT allowed potato cultivation 15–25 days earlier than CT. Although crop modeling did not show a significant increase in potential tuber yield when simulating the earlier planting of ZT, this advantage will be crucial in the future, considering that high-intensity rainfall events are increasing, flooding the fields and preventing crop cultivation. Alkalinity, carbonates, and anaerobic soil conditions drove the SQI, influencing the elements kept in the past rice cultivation with a concomitant effect in tuber yield. ZT is a promising technology that allows crop diversification based on soil sustainability and labor reduction in challenging agroecologies like Southwest Bangladesh. Socioeconomic studies into adoption and scaling approaches are necessary for a proper technological transfer.
Diets, Fruit and Vegetable Intake and Nutritional Status in Tanzania: Scoping Review
(Journal Article, 2024-12-11) Amunga, Dorcas; Hess, S.; Grant, F.; Kinabo, J.; Olney, Deanna K.
Globally, the intake of fruit and vegetables (F&V) is far below the recommended levels, contributing to various health challenges including micronutrient deficiencies and non‐communicable diseases. In Tanzania, where the triple burden of malnutrition persists, there is a need to identify gaps in evidence, better understand diets and F&V intake and identify promising interventions for improved intake. We conducted a scoping review to summarize the evidence on dietary intake, F&V intake and nutritional status in Tanzania. This included three separate literature searches in PubMed covering the years 2012–2023. A total of 62, 37 and 15 articles met predefined eligibility criteria for the review of overall diet, dietary intake of F&V and nutritional status, respectively. Identified studies suggest that overall dietary practices among all population groups were primarily based on carbohydrate‐rich foods, complementary feeding practices were suboptimal among young children and a low proportion of women of reproductive age (WRA) and pregnant and lactating women achieved minimum dietary diversity for women (MDD‐W). Across all population groups, F&V intake was below the recommended 400 g per day. Analysis of nutritional status in Tanzania in population representative surveys showed high stunting prevalence in children below 5 years of age, and a high prevalence of overweight and obesity among WRA, particularly in urban areas. Additional research is needed to understand better the complex interactions between diet and nutrition and health outcomes, and to identify efficient and cost‐effective strategies to improve overall dietary quality, including increasing F&V intake.
Agronomic and economic benefits of rice–sweetpotato rotation in lowland rice cropping systems in Uganda
(Journal Article, 2024-11-18) Kyalo, G.; Rajendran, S.; Alibu, S.; Zziwa, S.; McEwan, M.; Ekobu, M.; Okello, S.E.A.; Namanda, S.; Otim, M.H.; Lamo, J.; Mwanga, R.O.M.; Low, Jan W.
A crop rotation study was conducted in the Agoro Rice scheme from mid-2015 to 2017 to determine the effect of sweetpotato–rice rotation in the lowlands on financial returns and sweetpotato root, sweetpotato vine, and rice yields compared to monocropping. Treatments included crop rotations of sweetpotato–rice–sweetpotato, rice–sweetpotato–rice, rice–rice–rice (control), and sweetpotato–sweetpotato–sweetpotato (control). The study used the sweetpotato varieties NASPOT 11 (cream-fleshed), NASPOT 10 O, and Ejumula (both orange-fleshed) and the rice varieties Wita 9, Agoro, and Komboka. The results showed that mean sweetpotato root yields in the rotation treatment were significantly higher (28 t ha−1) than the control (19.8 t ha−1), representing a 47% gain in yield. Generally, the percentage gain in yield across years due to rotation ranged from 3 to 132%, depending on the variety. The total number of vine cuttings was significantly different between treatments and seasons (P < 0.001). Mean rice paddy yields in rotation were 8–35% higher than the control. The higher yields of sweetpotato in the rotation can be attributed to the rotation crop benefitting from residual fertilizers applied in rice in the previous season, while rice in the rotation crop could have benefited from the land preparation and establishment of the sweetpotato fields. The benefit of rotation for both crops varied by variety while the revenue-to-cost ratio varied by season and crop variety. Revenue-to-cost ratios for rotation and control treatments were greater than 1, indicating net profits were positive for both. The rotation generated 0.43 times more revenue than rice monocropping. Both rotation and monocropping systems generated profits, but rotation was 43% more profitable. In other words, if monocropping generates 1 dollar, rotation generates 1.43 dollars. The study concludes that rotation of sweetpotato with rice led to (1) increased yields of both rice and sweetpotatoes, (2) more profitable utilization of land, (3) enhanced availability of sweetpotato planting material at the beginning of the upland growing season, and (4) reduced the cost of land preparation for the main rice crop. Findings from this study show that there is great potential for diversification of rice-based cropping systems in Uganda, which will contribute to building sustainable food systems.
Research brief: Analysis of policy responses to seed, fertilizer, food and fuel shocks in three African Regional Economic Communities
(Journal Article, 2024-11-20) Lokosang, L.B.; Kirui, L.K.; Maru, J.; Karugia, Joseph T.; Bahta, Sirak T.; Enahoro, Dolapo K.
The COVID-19 pandemic and the ongoing Russia-Ukraine war had severe implications for global food security and nutrition. It was feared that food systems would be impacted negatively, especially food, seed, fertilizer, and fuel quantities required for agricultural production. The study aimed to ascertain the extent to which calls to action by AU policy organs, as well as recommendations by experts, to mitigate possible effects of the COVID-19 pandemic, were implemented at the national level across three of the five regional economic communities and whether they yielded any tangible impacts. The study conducted a desk review of literature and key informant interviews in 18 African countries. We found a wide range of varia-tions in terms of country responses to the pan-demic. Countries in the East African Community focused more on expanding targeted social protec-tion programs, Economic Community of West African States countries focused more on support-ing smallholder farmers and digital agriculture, and the Southern African Development Community focused on budgetary stimulus packages. We found a lack of coherence in responding to the crisis within each region to improve the supply and dis-tribution of food, seed, fertilizer, and fuel; thus, necessitating an immediate and aggressive imple-mentation of strategies aligned with continental and regional policy resolutions and recommenda-tions.
Effect of elevated temperature and CO2 on growth of two early-maturing potato (Solanum tuberosum L.) varieties
(Journal Article, 2024-11-14) Liu, C.; Li, Y.; Liu, Y.; Kear, P.; Feng, Y.; Wang, L.; Luo, M.; Li, J.
Climate change will significantly reduce potato yields across the world and have a profound impact on food security. However, the effects of changing climatic conditions on various traits of early-maturing potatoes at their different stages of growth are not clear. Therefore, 19 plant traits were investigated across the entire growth period of two major early-maturing potato varieties: Favorita and Zhongshu 5. These were grown in a temperature/CO2-controlled walk-in chamber under four treatments that simulated the changes predicted in these two climate factors by 2100: Control (ambient temperature 21 °C; ambient CO2 400 μmol mol-1), eT (elevated temperature 24 °C; ambient CO2 400 μmol mol-1), eCO2 (ambient temperature, 21 °C; elevated CO2 800 μmol mol-1), and eTeCO2 (elevated temperature 24 °C; elevated CO2 800 μmol mol-1). Elevating ambient temperature by 3 °C (eT), elevating CO2 concentration to 800 μmol mol-1 (eCO2), and a combination of both treatments (eTeCO2) brought forward potato tuber initiation by approximately 10 days. eT treatment reduced the yield of Favorita by 83% and Zhongshu 5 by 52%, but simultaneously elevating the CO2 concentration (eTeCO2) alleviated the negative effects of higher temperature on plant morphology and biomass. Favorita exhibited greater stability than Zhongshu 5 under all treatment conditions. These findings will guide the development, cultivation, and research of climate-resilient potatoes as an adaptation to climate change to strengthen food security.
Selectivity of new generation herbicide ‘Tembotrione’ under conservation agriculture-based maize (Zea mays) in maize-wheat-mungbean cropping system
(Journal Article, 2024-09) Roy, N.S.; Shekhawat, N.K.; Rathore, N.S.S.; Kumar, N.
An experiment was conducted at the ICAR-Indian Agricultural Research Institute in New Delhi during the rainy (Kharif) seasons of 2021–22 and 2022–23. The study aimed to evaluate the weed control efficiency of low dose new generation herbicide: tembotrione (34.4% SC) as a component of integrated weed management (IWM), on zero-till (ZT) and conventional till (CT) maize (Zea mays L.). The treatments were comprised of conventional tillage maize (M1: CT-M), conventional tillage maize with green manure from preceding green gram (M2: CT-M+GM), zero tillage maize with residue retention at 3 t/ha (M3: ZT-M+R), zero tillage maize with Sesbania co-culture as brown manuring (cover crop) (M4: ZT-M+BM) in the main plot and five weed control treatments, viz S1: Un- weeded check, S2: Pre +1 HW, S3: Pre + Post (tembotrione) @120g/ha, S4: Pre+ Post (Premix of Mesotrione+ Atrazine) @120 g/ha, S5: Weed free check (WFC) in the sub-plots were evaluated in split-plot design. It was ob- served that ZT-M+BM caused a considerable reduction in the population of broad-leaf weed, narrow leaf weed with sedges and total weeds (28.4% reduction at 60 days after sowing) compared to M1. The results also revealed that the sequential application of atrazine @750g/ha+pendimethalin @750g/ha(pre) followed by (fb.) tembotrione (34.4% SC) @120 g/ha (post) among the herbicide options reduced the weeds population (78.5%) and dry weight (81.3%) significantly than the un-weeded control (UWC). Maize yield attributes were higher in ZT with Sesbania co-culture (ZT-M+BM) than conventional-tilled treatments (CT-M). The application of atrazine @750g/ ha+pendimethalin @750g/ha (pre) fb. tembotrione @120 g/ha (post) combined with ZT-M+BM resulting in higher maize yield (6.88 t/ha) which was comparable with that in weed-free check (WFC). The post emergence (PoE) ap- plication of tembotrione (34.4% SC) @120 g/ha recorded highest weed control efficiency (86.2%), weed control in- dex (88.1%) and lowest value of weed index (7.04) when applied in the ZT-maize with sesbania as a cover crop. Therefore, combining zero tillage (ZT) with brown manure (Sesbania), along with atrazine and pendimethalin (@750g/ha each) as pre-emergence herbicides, and tembotrione (@120g/ha) as a post-emergence herbicide is recommended for effective weed control and high maize productivity in the North-Western Indo-Gangetic plains (IGP).
Estimation of Glacier Outline and Volume Changes in the Vilcanota Range Snow-Capped Mountains, Peru, Using Temporal Series of Landsat and a Combination of Satellite Radar and Aerial LIDAR Images
(Journal Article, 2024-10-20) Montoya-Jara, N.; Loayza, H.; Gutiérrez-Rosales, R.O.; Bueno, M.; Quiroz, R.
The Vilcanota is the second-largest snow-capped mountain range in Peru, featuring 380 individual glaciers, each with its own unique characteristics that must be studied independently. However, few studies have been conducted in the Vilcanota range to monitor and track the area and volume changes of the Suyuparina and Quisoquipina glaciers. Notably, there are only a few studies that have approached this issue using LIDAR technology. Our methodology is based on a combination of optical, radar and LIDAR data sources, which allowed for constructing coherent temporal series for the both the perimeter and volume changes of the Suyuparina and Quisoquipina glaciers while accounting for the uncertainty in the perimeter detection procedure. Our results indicated that, from 1990 to 2013, there was a reduction in snow cover of 12,694.35 m2 per year for Quisoquipina and 16,599.2 m2 per year for Suyuparina. This represents a loss of 12.18% for Quisoquipina and 22.45% for Suyuparina. From 2006 to 2013, the volume of the Quisoquipina glacier decreased from 11.73 km3 in 2006 to 11.04 km3 in 2010, while the Suyuparina glacier decreased from 6.26 km3 to 5.93 km3. Likewise, when analyzing the correlation between glacier area and precipitation, a moderate inverse correlation (R = −0.52, p < 0.05) was found for Quisoquipina. In contrast, the correlation for Suyuparina was low and nonsignificant, showing inconsistency in the effect of precipitation. Additionally, the correlation between the snow cover area and the annual mean air temperature (R = −0.34, p > 0.05) and annual minimum air temperature (R = −0.36, p > 0.05) was low, inverse, and not significant for Quisoquipina. Meanwhile, snow cover on Suyuparina had a low nonsignificant correlation (R = −0.31, p > 0.05) with the annual maximum air temperature, indicating a minimal influence of the measured climatic variables near this glacier on its retreat. In general, it was possible to establish a reduction in both the area and volume of the Suyuparina and Quisoquipina glaciers based on freely accessible remote sensing data.
Color and Grey-Level Co-Occurrence Matrix Analysis for Predicting Sensory and Biochemical Traits in Sweet Potato and Potato
(Journal Article, 2024-10-30) Nantongo, J.S.; Serunkuma, E.; Nakitto, M.; Kitalikyawe, J.; Mendes, T.; Davrieux, F.; Ssali, R.T.
In sweet potato and potato, sensory traits are critical for acceptance by consumers, growers, and traders, hence underpinning the success or failure of a new cultivar. A quick analytical method for the sensory traits could expedite the selection process in breeding programs. In this paper, the relationship between sensory panel and instrumental color plus texture features was evaluated. Results have shown a high correlation between the sensory panel and instrumental color in both sweet potato (up to r = 0.84) and potato (r > 0.78), implying that imaging is a potential alternative to the sensory panel for color scoring. High correlations between sensory panel aroma and flavor with instrumental color were detected (up to r = 0.66), although the validity of these correlations needs to be tested. With instrumental color and texture parameters as predictors, low to moderate accuracy was detected in the machine learning models developed to predict sensory panel traits. Overall, the performance of the eXtreme Gradient Boosting (XGboost) was comparable to the radial-based support vector machine (NL-SVM) algorithm, and these could be used for the initial selection of genotypes for aromas and flavors (r2 = 0.64–0.72) and texture attributes like moisture or mealiness (r2 > 50). Among the chemical properties screened in sweet potato, only starch showed a moderate correlation with sensory features like mealiness (r = 0.54) and instrumental color (r = 0.65). From the results, we can conclude that the instrumental scores of color are equivalent to those scored by the sensory panel, and the former could be adopted for quick analysis. Further investigations may be required to understand the association between color and aroma or flavor.
Supply and Demand of Processed Potato Products in Kenya, Rwanda, and Uganda: Variety Requirements of Processing Companies and Implications for Trait Prioritization for Breeding
(Journal Article, 2024-10) Naziri, D.; Devaux, A.; Hareau, G.; Wauters, P.
The potato processing industry in Kenya, Rwanda, and Uganda is expanding rapidly. This study assesses the current situation and outlook of the local industrial potato processing sector and the alignment of the industry’s variety requirements with the priorities set by breeders. Currently, potato processing companies in the three countries use both varieties selected locally from public international germplasm and varieties introduced by Dutch seed companies, and their suitability for processing is discussed as well. Overall, the processing industry pays high attention to traits affecting processing efficiency and consumers’ acceptance while breeders, in spite of being aware of the characteristics required for processing varieties, are more focused on traits related to production and disease resistance. As the processing sector develops further, breeders will have to pay increased attention to the progressively stricter requirements of the industry, striking the right balance between farmers’ and processors’ variety requirements. While their opinions on the farmers’ acceptability of processing varieties diverge, breeders and industry agree about the challenges represented by the limited access to quality seed and poor business linkages between value chain actors in securing the supply of varieties suitable for processing. Based on these findings, it is recommended to pay more attention to both the development of dual-purpose varieties and the strengthening of the potato value chain through the improvement of business linkages between seed producers, farmers, and processing companies.
Effect of Gas Exchange Rate, Vessel Type, Planting Density, and Genotype on Growth, Photosynthetic Activity, and Ion Uptake of In Vitro Potato Plants
(Journal Article, 2024-10-09) Vollmer, R.; Espirilla, J.; Espinoza, A.; Villagaray, R.; Castro, M.; Pineda, S.; Sánchez, J.C.; Mello, A.F.S.; Azevedo, V.C.R.
The growth of high-quality in vitro potato plants (Solanum stenotomum subsp. stenotomum, Solanum stenotomum subsp. goniocalyx, and Solanum tuberosum subsp. andigena) is affected by multiple biological, operational, and environmental factors. Research on in vitro culture is frequently focused on the species, explant, composition of the culture medium, and incubation conditions, but only limited information is available on the effect of the gas exchange rate and volume of in vitro culture vessels under variable planting densities. In the present study, these factors were evaluated with a set of seven diverse potato landraces. The results were compared to the plants’ responses in routinely used in vitro culture vessels, i.e., 13 × 100 mm and 25 × 150 mm test tubes, and GA7® magenta vessels. In vitro potato plants grown in plastic vessels equipped with a HEPA filter delivering a high gas exchange rate developed thicker stems (0.95 mm), a higher total average leaf area (2.51 cm2), increased chlorophyll content in leaves (32.2 ppm), and lower moisture content in their tissues (90.1%) compared to filter systems with lower gas exchange rates. A high planting density of 10 × 10 plants per vessel (360 and 870 mL) negatively affected the average stem width and root length but increased the plant height (3.4 cm). High fluctuations of ion-uptake of NO3−, Ca++, K+, and Na+ were observed between genotypes, with some accessions having a 4.6-times higher Ca++-ion concentration in their tissues (190–234 ppm). The in vitro plants developed more robust stems, longer roots, and larger leaves within in vitro culture vessels equipped with a HEPA filter (high gas exchange rate) compared to the control vessels, in contrast to the chlorophyll content in leaves, which was higher in plants grown in narrow test tubes. Depending on the purpose of the subculture of in vitro plants, their growth and development can be molded using different gas exchange rates, planting densities, and vessel volumes.
Public and private institutional arrangements for early generation seed production: Cassava seed value chains in Southeast Asia
(Journal Article, 2024-12) Delaquis, E.; Almekinders, Conny J.M.; Haan, Stef de; Newby, J.C.; Thuy, C.T.L.; Srean, P.; Wannarat, W.; Aiemnaka, P.; Rojanaridpiched, C.; Nhan, P.T.; Kang, P.; Struik, P.C.
CONTEXT Early generation seed (EGS) production and delivery pathways are critical components of so-called formal seed systems, of principal importance in the release of improved varieties into national seed systems. Vegetatively propagated crops (VPCs), with clonal reproductive ability and considerable differences in production and dissemination patterns from sexually propagated crops, often challenge generalized assumptions about ‘business models’ for private sector-led EGS production. OBJECTIVE We evaluate production trends and institutional arrangements for early generation ‘seed’ (stem cutting) production in the Greater Mekong Subregion of Southeast Asia to compare models, stakeholders, production pathways, and economic efficiency. We systematically document three cases of formal EGS production underpinning this globally important agricultural commodity, and contextualize their development in regional cassava production trends. We then interrogate whether the observed models support common assumptions in contemporary debates about how VPC seed system development, in particular the logic of public and private participation. METHODS To contextualize EGS initiatives, we compiled district-level production data and processing factory locations from national sources across the Greater Mekong subregion, paired with data on varietal releases and international trade of cassava products. To evaluate institutional arrangements for cassava EGS production in this context, we conducted ten key informant interviews with stakeholders involved with three case studies in Cambodia, Thailand, and Vietnam. Using a seed value chains framework, we compared institutional participation, seed multiplication practices, and partial budgets of each case. RESULTS AND CONCLUSIONS The three cases represent diverse institutional arrangements that don't exhibit seed company-led, profit-motivated structures often recommended by experts. Despite the commercial nature of export-oriented Southeast Asian cassava products, public involvement remained central in cassava breeding and EGS delivery models, implemented via different actors and multiplication stages. Case histories and partial production budgets describe institutional arrangements with variable points of subsidy along the value chain, resulting in positive effects on varietal turnover and cassava production across the region. SIGNIFICANCE While private sector involvement was significant and variable, public involvement remains important, even for highly commercialized crops like cassava. Contrary to common assumptions, successful cassava EGS systems in Southeast Asia have initiated impressive impacts without pursuing conventionally profit-oriented seed business models. Value chain approaches reveal backing EGS yields tangible downstream benefits, but for VPCs additional innovations are required to ensure benefits support the sustainability of expensive upstream multiplication stages. Approaches considering institutional participation along seed and product value chains can identify mechanisms for doing so beyond conventional seed commercialization.

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