#landraces

Karnal bunt (KB) disease is one of the most important challenges posed on of wheat (Triticum aestivum L.) industry of Pakistan because of itsinclusionin quarantine list around the globe. This disease is caused by the fungus Tilletia indica M. (Neovossia indica). It affects the grain quality of wheat and hampers its movement in international market resulting in economic losses. Presence of >3% infected grains in wheat lot makes it unsuitable for human consumption. Eradication of this disease is very difficult as no resistant cultivar has been found against KB in Pakistan so far. Genome wide association study (GWAS) was conducted on a set of 199 wheat germplasm collected from Pakistan. In this study 31,000 single nucleotide polymorphism markers were developed by 90K SNP array technology. A linear mixed model in GWAS, accounting for population structure, was fitted to identify significant genomic regions [-log(P) ≥ 4.0] on 6 different chromosomes i.e. 1A, 1D, 2D, 3B, 4A, 5A with novel loci. Candidate genes, through wheat genome assembly, were identified as putative genes related to KB resistance including kinase like protein family. The results of this study can be useful in wheat breeding through marker assisted selection for KB resistant varieties.

The experiments were conducted to evaluate the performance of Bambara groundnut landraces to heat and water stress. Mottled brown, black, mottled white and white landraces were subjected to watering regimes (watering once in a week till maturity and watering once in a week till the 30th day after planting. The drought study was a 4 × 2 factorial experiment laid in a complete randomized design with three replicates. Data collected included canopy spread, plant height, number of stem and leaves, first flower appearance and days to senescence on different sampling occasions (20, 45 and 60 days after sowing). Heat tolerance of landraces was determined using cell membrane thermostability test. The experiment revealed that the crop has different canopy forms which were significantly different among the various landraces. Watering up to 30 days, black landrace produced shorter plants whiles white landrace produced taller plants as compared to their respective heights when they were watered to maturity. The number of stems and leaves was significantly influenced by the watering regime. Watering till maturity decreased days to flowering and also increased days to senescence compared to plants for which watering was withheld after 30 days of growth. The cell membrane thermostability test revealed that mottled brown landrace was able to sustain significantly less injury as compared to the other landraces. The results of this study reinforces the knowledge that Bambara seed landraces can survive under harsh climate conditions.

The experiments were conducted to evaluate the performance of Bambara groundnut landraces to heat and water stress. Mottled brown, black, mottled white and white landraces were subjected to watering regimes (watering once in a week till maturity and watering once in a week till the 30th day after planting. The drought study was a 4 × 2 factorial experiment laid in a complete randomized design with three replicates. Data collected included canopy spread, plant height, number of stem and leaves, first flower appearance and days to senescence on different sampling occasions (20, 45 and 60 days after sowing). Heat tolerance of landraces was determined using cell membrane thermostability test. The experiment revealed that the crop has different canopy forms which were significantly different among the various landraces. Watering up to 30 days, black landrace produced shorter plants whiles white landrace produced taller plants as compared to their respective heights when they were watered to maturity. The number of stems and leaves was significantly influenced by the watering regime. Watering till maturity decreased days to flowering and also increased days to senescence compared to plants for which watering was withheld after 30 days of growth. The cell membrane thermostability test revealed that mottled brown landrace was able to sustain significantly less injury as compared to the other landraces. The results of this study reinforces the knowledge that Bambara seed landraces can survive under harsh climate conditions.