Enhanced Biotic-stress Tolerance of Pulses Towards Sustainable Intensification of Cropping Systems for Climate-change Adaptation

Background:

Pulses are important food crops in smallholder agriculture in Africa and Asia, and in several instances, they are also grown for fodder. Because of their vital role in human and soil health, farmers grow these crops with cereals to not only meet the diversified food needs but also for maintaining soil health. Leguminous crops are known to add nitrogen to the soil through biological nitrogen fixation and can be grown without added nitrogen fertilizers thus contributing to reduced carbon footprint. Among the pulse crops, chickpea, cowpea, and lentil are popular choices for the smallholder farmers in South Asia and Sub-Saharan Africa as they thrive well even under limited external inputs. These crops are the mainstay of dryland farming systems.

The productivity of pulses is generally low in most developing countries, average yields ranging from about 0.5 to a little over 1 tonne per ha. Yields are reduced further by the incidence of several biotic and abiotic stresses. The fact that pulses are self-pollinated has led to a narrow genetic diversity in many of these crops.

In this CRP, mutation induction and associated genomics technologies will be used for productivity improvement of three pulses, namely, chickpea, cowpea and lentil, which together account for 40% of global pulses’ production. The research focus is on enhancing the tolerances of: (1) chickpea to the pod borer, Helicoverpa armigera; (2) cowpea to the bod borer, Maruca vitrata, and (3) lentil to the disease, Stemphylium blight. Towards this end, the CRP, with the expected participation of the National Agricultural Research System of countries where the crops are grown extensively, shall over a period of four to five years, generate mutant populations, including advanced lines, and develop, validate and publish genotyping and phenotyping protocols.

Mutation induction is an established means to generate heritable variation in crops and therefore holds great promise to diversify further the genetic base of pulses, enhancing their adaptation to the pressures induced by the effects of climate change, especially the frequent emergence of new biotypes and strains of pests and diseases. The Mutant Variety Database of the IAEA identifies 23, 18 and 13 varieties, respectively, of chickpea, lentil and cowpea, released from past efforts in mutation breeding using irradiation (gamma rays) and chemical (EMS) mutations.

CRP Overall objective:

This CRP aims to develop genetic resources through induced mutations and associated genomic tools for accelerated adaptation of pulses-based cropping systems to climate change.

Specific Research Objectives:

  • To generate genetic diversity in chickpea, cowpea and lentil through mutagenesis for resistance to Helicoverpa armigera, Maruca vitrata and Stemphylium botryosum, respectively.
  • To develop and/or refine phenotyping tools to facilitate precise (confident) and efficient selection of biotic-stress resistance in selected pulse crops.
  • To develop genomic tools for accelerated variety development for the selected pulse crops and associated traits of interest.

Outputs:

  • Mutant population(s) generated for chickpea, cowpea and lentil.
  • Phenotyping tools developed for the identification of resistant germplasm.
  • Improved lines identified for traits of interest.
  • Molecular markers and associated protocols developed for variety development/improvement.
  • Scientific publications produced.
  • Protocols and training manuals developed and disseminated.

Project Officer:

S. Sivasankar and N. Warthmann