Evaluation of New Super-early Pigeonpea Lines for Agronomic Performance and Adaptation in India

Pigeonpea [Cajanus cajan (L.) Millspaugh] is a multi-purpose legume crop used mainly for human consumption in the form of processed split dry peas (dal) or fresh as a vegetable. In addition to food, pigeonpea can also be used for a number of other purposes (ie, feed, fodder, fuel, fertilizer). India is the number one producer and consumer of pigeonpea, but still needs to import around 500,000 tons per year to satisfy the internal demand. Increasing the area under pigeonpea cultivation could contribute to increased production, but this would only be possible by expanding pigeonpea cultivation to non-traditional areas including wider latitudes, higher altitudes and marginal lands, and to fit in the narrow window of time between harvest and planting of important cereal crops

Water-logging: A Forgotten Problem in Pigeonpea

Water-logging is emerging as a pressing concern at the backdrop of climate change in recent years A global report on climate change has projected a 0.5 – 1.2°C rise in temperatures by 2020, resulting in unpredictable and excessive rainGlobally, an area of more than 40 million ha is affected by water-logging In India, an area of 8.53 million ha is affected by water-logging with an estimated loss of >2 million tons of food grains every year

Integrated physiological and molecular approaches to improvement of abiotic stress tolerance in two pulse crops of the semi-arid tropics

Chickpea (Cicer arietinum L.) and pigeonpea [Cajanus cajan L. (Millsp.)] play an important role in mitigating protein malnutrition for millions of poor vegetarians living in regions of the semi-arid tropics. Abiotic stresses such as excess and limited soil moisture (water-logging and drought), heat and chilling (high and low temperature stresses), soil salinity, and acidity are major yield constraints, as these two crops are grown mostly under rainfed conditions in risk-prone marginal and degraded lands with few or no inputs. Losses due to such stresses vary from 30% to 100% depending on their severity. The literature abounds in basic information concerning screening techniques, physiological mechanisms, and genetics of traits associated with resistance/tolerance to abiotic stresses in these two crops. However, the final outcome in terms of resistant/tolerant varieties has been far from satisfactory. This situation calls for improving selection efficiency through precise phenotyping and genotyping under high-throughput controlled conditions using modern tools of genomics. In this review, we suggest that an integrated approach combining advances from genetics, physiology, and biotechnology needs to be used for higher precision and efficiency of breeding programs aimed at improving abiotic stress tolerance in both chickpea and pigeonpea

Ensuring the Success of Pigeonpea Hybrids by Focusing on Purity of Parental Lines and Appropriate Management Practices

Pigeonpea [Cajanus cajan (L.) Millsp.] is an important legume crop, grown mainly in the semi-arid tropics of Asia, Africa, Latin America, and the Caribbean. The total world area planted with pigeonpea is 4.6 million ha. India is the number one producer (3.5 million ha) of pigeonpea; despite this, there is not sufficient amount available to meet the nutritional needs of the large and mainly vegetarian resource-poor population and importation of pigeonpea from other countries like Myanmar and parts of Africa is needed to fulfill the country needs. Although dozens of pigeonpea varieties have been released, the productivity of pigeonpea has remained stagnant at around 700 kg ha- 1. This is mainly due to various genetic, management, abiotic, and abiotic constraints. Since the area of pigeonpea cultivation is not likely to be increased, the emphasis moves to break the yield gap and to increase productivity by genetic enhancement of germplasm by incorporating tolerance to biotic and abiotic stresses, and by replacing the traditional varieties with the newly developed options

Ensuring Genetic Purity of Pigeonpea Hybrids by Incorporating a Naked-Eye Polymorphic Marker in A and B Lines

To enhance the productivity of pigeonpea [Cajanus cajan (L.) Millspaugh] a hybrid breeding technology, based on the cytoplasmic nuclear male-sterility (CMS) system and partial natural outcrossing, is currently been used. However, there are diffi culties to maintain genetic purity of the hybrids and their parents. The incorporation of an easily identifi able morphological marker (naked eye polymorphism [NEP]) could be used to determine seed purity. The morphological marker selected for this study, obcordate leaf, is not present in cultivated pigeonpea; it is inherited as a single recessive gene and can be observed soon after planting (approx. 6 wk). To incorporate the obcordate leaf shape into hybrid parents, the trait was transferred from the germplasm accession ICP 5529 into male-sterile (A lines) and the corresponding maintainers (B lines). The hybrids derived from crosses involving obcordate leaf A lines and normal leaf fertility restorers (R lines) were fully fertile and had normal lanceolate leaves; thus the difference between A line and hybrids was clear. The use of obcordate leaf as a NEP marker in pigeonpea would contribute to preserve parental line purity and confi rm hybrid status

Harnessing the Potential of Crop Wild Relatives through Genomics Tools for Pigeonpea Improvement

Cultivated pigeonpea germplasm has a narrow genetic base due to the bottlenecks caused by domestication and breeding from a small number of genotypes. Pigeonpea genetic improvement has witnessed a slow pace due to low genetic diversity and to the scarce genomics resources. To address these challenges, wild relatives of pigeonpea which represent an unexploited resource of vast genetic variation can be incorporated in breeding programmes facilitating the broadening of genetic base. Although interspecific hybridization has not been commercially successful in pigeonpea, it has played an important role in the development of the cytoplasmic male sterility (CMS) system. Recent years however have witnessed the development of genomics resources at large scale in the crop which has remained untouched with genomics revolution in the past. These resources, together with advances in genomics platform such as high throughput genotyping assays and next generation sequencing technologies and modern genetics and breeding approaches will accelerate harnessing natural variation for pigeonpea improvement

GGE biplot based assessment of yield stability, adaptability and mega-environment characterization for hybrid pigeonpea (Cajanus cajan)

GGE biplot methodology is a powerful tool to study relationship among test environments (E), genotypes (G) and genotype-by-environment interaction (GE). Present study was conducted on 10 short-duration genotypes in five test environments for two years, and 16 medium-duration genotypes in six test locations for three years in randomized complete block design with two replications. In short-maturity group three mega-environments (ME) were found—ME1 comprised of Phaltan, Patancheru and Hyderabad1; ME2 and 3 constituted Jalna and Aurangabad, respectively. In scenario of limited resources, Patancheru may be a good testing location for general adaptability of short-duration hybrids, while Aurangabad and Hyderabad1 may be right environments for testing specific adaptation of short-duration cultivars in pigeonpea. ICPH 2433 was a winning genotype in ME1 in terms of high yield and stability. In medium-maturity group, two MEs were observed. Jalna, Jalna 1, Parbhani and Hyderabad grouped together as ME1, while Patancheru and Phaltan formed the second mega-environment (ME2). Parbhani was found to be most representative of all the six test locations. Jalna (ME1) and Phaltan (ME2) produced longest environment vectors, and hence may be regarded as highly discriminating. In mediummaturity group ICPH 2673 was found to be stable and high-yielding genotype for ME

Breeding for Earliness in Pigeonpea: Development of New Determinate and Nondeterminate Lines

Considering the increasing demand for pigeonpea [Cajanus cajan (L.) Millsp.], especially in India, breeders have realized the need to develop high-yielding, super-early maturing (<90 d) lines that could be planted in a wider range of latitudes and/or altitudes to enhance the crop adaptation and to diversify the legume-based cropping systems. The International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) initiated a breeding program in 2006 to develop “super-early” (flowering in <50 d) determinate (DT) and nondeterminate (NDT) pigeonpea lines. Eleven parental lines with days to 50% flowering ranging from 49 d (MN 5) to 103 d (ICP 6974) were crossed using a full diallel mating design. A pedigree-based approach was followed to select for early flowering. The selection gain was larger initially (reduction of 7 d) but there was less reduction (2 d) from F3 to F4. Determinate and NDT lines that flowered in 45 to 56 d at ICRISAT-Patancheru reached advanced (F5 and F6) generations. The newly developed lines flowered and matured at a higher latitudes (tested at 30° N vs. 17° N) and altitudes (tested at 1250, 545, and 247 m asl). These lines could be used in new cropping systems (i.e., pigeonpea–wheat [Triticum aestivum L.]) that would allow expanding pigeonpea production to nontraditional planting areas (i.e., wider latitudes and higher altitudes) and could even offer wider planting time flexibility to farmers

GGE biplot based assessment of yield stability, adaptability and mega-environment characterization for hybrid pigeon pea (Cajanus cajan

ABSTRACT GGE biplot methodology is a powerful tool to study relationship among test environments (E), genotypes (G) and genotype-by-environment interaction (GE). Present study was conducted on 10 short-duration genotypes in five test environments for two years, and 16 medium-duration genotypes in six test locations for three years in randomized complete block design with two replications. In short-maturity group three mega-environments (ME) were found-ME1 comprised of Phaltan, Patancheru and Hyderabad1; ME2 and 3 constituted Jalna and Aurangabad, respectively. In scenario of limited resources, Patancheru may be a good testing location for general adaptability of short-duration hybrids, while Aurangabad and Hyderabad1 may be right environments for testing specific adaptation of short-duration cultivars in pigeonpea. ICPH 2433 was a winning genotype in ME1 in terms of high yield and stability. In medium-maturity group, two MEs were observed. Jalna, Jalna 1, Parbhani and Hyderabad grouped together as ME1, while Patancheru and Phaltan formed the second mega-environment (ME2). Parbhani was found to be most representative of all the six test locations. Jalna (ME1) and Phaltan (ME2) produced longest environment vectors, and hence may be regarded as highly discriminating. In mediummaturity group ICPH 2673 was found to be stable and high-yielding genotype for ME1

Development of ‘super-early’ pigeonpeas with good yield potential from early × early crosses

To enhance the adaptability of pigeonpea at higher latitude and altitude, a breeding program was initiated at ICRISAT involving different sources of early-maturity. A full diallel mating design involving 11 early-maturing lines were used as parents. In F2–F5 generations, selection was followed for early flowering and maturity, grain yield and 100-seed weight by pedigree method. Four brown seeded (ICPX 060064-4-6-10, ICPX 060077-6-5-14, ICPX 060064-4-6-2 and ICPX 060063-11-8-4) and one cream seeded (ICPX 060036-13-4-8) F4/F5 indeterminate super-early progenies that matured, respectively 25 and 23 days earlier than the control cultivar ICPL 88039 were recovered. ICPX 060036-13-4-8 recorded 107% and 34% grain yield advantage over the checks ICPL 86022 and ICPL 88039, respectively. These super-early lines were derived from crosses involving AL 1518-2 × ICPL 85010, AL 1621 × MN 5, AL 1518-2 × MN 8 and MN 8 × AL 1518-2. Other super-early progenies [ICPX 060016-10-8-1 (from MN 1 × AL 1518-2 cross) and ICPX 060017-12-12-20 (from MN 1 × AL 1621 cross)] with greater 100-seed weight were also recovered. Besides serving as excellent donors for earliness, these lines may be photo/thermo insensitive. These super-early pigeonpea lines may open new niches for this crop and help in intensification of farming system