Cross breeding could boost chickpea crops
a feat that to date has been extremely difficult to undertake. The
programme is aiming to develop chickpeas that are more resistant to
disease, in turn boosting crop yields.
A scientific team based at the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), says it has been able to obtain healthy interspecific hybrids of chickpea with the development of embryo rescue and tissue culture techniques by crossing the C. arietinum variety with wild species C. bijugum.
The scientific team says that this is the first step towards development of new hybrids by crossing cultivated varieties with wild species, an achievement that has so far proved highly illusive.
India leads the production of chickpea (Cicer arietinum), producing 5,770,000 million tonnes per year, according to current FAO estimates. But the world's third most important legume rests on a narrow genetic base because of its single domestication and its self-pollinating nature makingit very difficult to engineer its genetic base.
One of the best proven means to broaden the genetic base of the crop, and also to introduce newer sources of resistance to various biotic and abiotic constraints, is to create interspecific hybrids of the plant by utilizing the wild species of chickpea.
By observing the genetic make up of wild chickpea, scientists have discovered two closely related wild species - namely C. reticulatum and C. echinospermum - are easier to use in breeding programmes. None of the remaining 41 wild species of wild chickpea can be cross fertilized due to serious hybridization barriers, such as lack of post-zygotic growth.
The ICRISAT research group developed embryo rescue and tissue culturetechniques for chickpea and were able to obtain healthy hybrids bycrossing C. arietinum with C. bijugum. In turn, the team believes thatthis is the first time that green hybrid plants were produced betweencultivated chickpea and the wild species C. bijugum.
"These newly developed chickpea are not genetic male sterile hybrids," said Nalini Mallikarjuna of ICRISAT.
The team has crossed an incompatible wild species C. bijugum with cultivated chickpea and hybrids have been produced by the use of embryo rescue and in vitro regeneration techniques.
Cicer bijugum used in the crossing program has many desirable characters such as resistance to Ascochyta blight, botrytis grey mold and to Helicoverpa- the menacing pod borer. It is supposed that some of these traits may occur there in the hybrids.
Although it is difficult to gauge the extent to which this might help to improve crop yields at this stage of the programme, crossing the cultivated and wild breeds of chickpea is expected to produce a hardy plant that will be able to stand up better to harsh weather and pest attacks, as well as producing a higher yield of chickpeas per plant.
