Castor (Ricinus communis L.) is a vital industrial oilseed crop with an indeterminate growth habit, often leading to excessive branching that reduces seed quality and yield. This chapter highlights the agronomic practice of nipping—removal of internodal buds on primary, secondary, and tertiary branches—to optimize spike development and improve yield. Nipping enhances air circulation, reduces disease incidence (e.g., botrytis), and improves the source–sink relationship for better photosynthate allocation. When combined with proper nutrition and spacing, nipping significantly increases oil yield and supports healthier crop stands. This practice is especially relevant for dryland farming systems aiming to boost productivity and farmer income sustainably.
Tag: agronomic practices
Climate change vulnerability and drivers of low maize yields under smallholder farming systems in semi-arid area of Marange in Zimbabwe
In Zimbabwe’s semi-arid Marange region, smallholder farmers continue to grow maize under rain-fed conditions despite high vulnerability to climate change and extremely low yields. This study, based on data from 107 households, found that maize yields averaged just 355 kg/ha, with wide variation linked to agronomic practices and access to information. Techniques such as planting basins, mulching, and strategic field placement improved yields, while socio-economic factors like access to extension services and weather data also played a role. However, overall productivity remains critically low. The findings highlight the urgent need for integrated interventions—improved agronomy, land management, and climate information access—to sustainably enhance maize production in vulnerable farming systems.
Biofuel from Jatropha curcas: opportuities, challenges and development perspectives
With soaring petroleum prices, the idea of converting agriculture to also produce energy has become a widespread goal of agricultural policies and research. Jatropha curcas is known to thrive with limited amounts of water, nutrients and capital inputs. It is seen as an option to cultivate comparatively marginal lands to produce oil rich seeds for biodiesel, generate additional income, reduce greenhouse gas emissions, and possibly help to rehabilitate degraded land.
Biodiversity loss, agricultural development, and sustainability
Research by the Alternatives to Slash-and-Burn (ASB) Consortium in Sumatra provides little support for the original perception ‘poverty causes people to migrate to the forests, but they don’t know how to manage the soils, which forces them to move on and open new forest, leaving a trail of degraded lands behind’. However, ASB research also shows that the land use systems that follow forest conversion differ significantly in the profitability and impacts on biodiversity. For example, farmers have developed agroforests, based on rubber, damar and other local or introduced trees, as sustainable and profitable alternatives to shifting cultivation, but these opportunities have stimulated rather than slowed down forest conversion in the absence of active boundary enforcement mechanisms for natural areas. Although agroforests can maintain part of the biodiversity of the originsl forests, they are no substitute for full protection of biodiversity in dedicated natural areas and conservation reserves.