Repositorio Nacional

A 3-year field experiment was setup to address the threat of underground water depletion and sustainability of agrifood systems. Subsurface drip irrigation (SDI) system combined with nitrogen management under conservation agriculture-based (CA) maize-wheat system (MWS) effects on crop yields, irrigation water productivity (WPi), nitrogen use efficiency (NUE) and profitability. Grain yields of maize, wheat, and MWS in the SDI with 100% recommended N were significantly higher by 15.8%, 5.2% and 11.2%, respectively, than conventional furrow/flood irrigation (CT-FI) system. System irrigation water savings (~ 55%) and the mean WPi were higher in maize, wheat, and MWS under the SDI than CT-FI system. There was saving of 25% of fertilizer N in maize and MWS whereas no saving of N was observed in wheat. Net returns from MWS were significantly higher (USD 265) under SDI with 100% N (with no subsidy) than CT-FI system despite with higher cost of production. The net returns were increased by 47% when considering a subsidy of 80% on laying SDI system. Our results showed a great potential of complementing CA with SDI and N management to maximize productivity, NUE, and WPi, which may be economically beneficial and environmentally sound in MWS in Trans-IGP of South Asia.

Subsurface Drip Irrigation Nitrogen Management Irrigation Water Productivity Water Savings CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA IRRIGATION WATER NITROGEN-USE EFFICIENCY CONSERVATION AGRICULTURE MAIZE WHEAT

Maize seed aid and seed systems development: Opportunities for synergies in Uganda

Jason Donovan Rachel Voss Pieter Rutsaert (2024, [Artículo])

In the name of food security, governments and NGOs purchase large volumes of maize seed in non-relief situations to provide at reduced or no cost to producers. At the same time, efforts to build formal maize seed systems have been frustrated by slow turnover rates – the dominance of older seed products in the market over newer, higher performing ones. Under certain conditions, governments and NGO seed aid purchases can support formal seed systems development in three ways: i) support increased producer awareness of new products, ii) support local private seed industry development, and iii) advance equity goals by targeting aid to the most vulnerable of producers who lack the capacity to purchase seeds. This study explores the objectives and activities of seed aid programmes in Uganda and their interactions with the maize seed sector. We draw insights from interviews with representatives of seed companies, NGOs and government agencies, as well as focus group discussions with producers. The findings indicated that seed aid programme objectives are largely disconnected from broader seed systems development goals. There is little evidence of public-private collaboration in design of these programmes. Better designed programs have the potential to align with varietal turnover objectives, commercial sector development and targeting of underserved markets could promote equity and ‘crowd in’ demand.

Seed Business Varietal Turnover Seed Aid CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA SEED SEED SYSTEMS SOCIAL INCLUSION MAIZE

Stage-gate advancement and testing strategies for Product Development at CIMMYT

Berhanu Tadesse Ertiro (2022, [Objeto de congreso])

CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA STAGES BREEDING MAIZE TESTING

Occurrence and Distribution of Physiological Races of Exserohilum turcicum in Maize Growing Regions of Mexico

Alexander Loladze Mateo Vargas Hernández amos Alakonya (2022, [Artículo])

CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA SETOSPHAERIA TURCICA MAIZE FOLIAR DISEASES PHYSIOLOGICAL RACES

Weed management and tillage effect on rainfed maize production in three agro-ecologies in Mexico

Simon Fonteyne Abel Jaime Leal González Rausel Ovando Ravi Gopal Singh Nele Verhulst (2022, [Artículo])

Maize (Zea mays L.) is grown in a wide range of agro-ecological environments and production systems across Mexico. Weeds are a major constraint on maize grain yield, but knowledge regarding the best weed management methods is lacking. In many production systems, reducing tillage could lessen land degradation and production costs, but changes in tillage might require changes in weed management. This study evaluated weed dynamics and rainfed maize yield under five weed management treatments (pre-emergence herbicide, post-emergence herbicide, pre-emergence + post-emergence herbicide, manual weed control, and no control) and three tillage methods (conventional, minimum and zero tillage) in three agro-ecologically distinct regions of the state of Oaxaca, Mexico, in 2016 and 2017. In the temperate Mixteca region, weeds reduced maize grain yields by as much as 92% and the long-growing season required post-emergence weed control, which gave significantly higher yields. In the hot, humid Papaloapan region, weeds reduced maize yields up to 63% and pre-emergence weed control resulted in significantly higher yields than treatments with post-emergence control only. In the semi-arid Valles Centrales region, weeds reduced maize yields by as much as 65%, but weed management was not always effective in increasing maize yield or net profitability. The most effective weed management treatments tended to be similar for the three tillage systems at each site, although weed pressure and the potential yield reduction by weeds tended to be higher under zero tillage than minimum or conventional tillage. No single best option for weed management was found across sites or tillage systems. More research, in which non-chemical methods should not be overlooked, is thus needed to determine the most effective weed management methods for the diverse maize production systems across Mexico.

Corn Integrated Weed Management Manual Weed Control CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA MAIZE WEED CONTROL MINIMUM TILLAGE ZERO TILLAGE