The tetraploid species Gossypium hirsutum is cultivated widely throughout the world with high yield and moderate fiber quality, but its genetic basis is narrow. A set of 107 introgression lines (ILs) was developed with an interspecific cross using G. hirsutum acc. 4105 as the recurrent parent and G. tomentosum as the donor parent. A specific locus amplified fragment sequencing (SLAF-seq) strategy was used to obtain high-throughput single nucleotide polymorphism (SNP) markers. In total, 3157 high-quality SNP markers were obtained and further used for identification of quantitative trait loci (QTLs) for fiber quality and yield traits evaluated in multiple environments. In total, 74 QTLs were detected that were associated with five fiber quality traits (30 QTLs) and eight yield traits (44 QTLs), with 2.02–30.15% of the phenotypic variance explained (PVE), and 69 markers were found to be associated with these thirteen traits. Eleven chromosomes in the A sub-genome (At) harbored 47 QTLs, and nine chromosomes in the D sub-genome (Dt) harbored 27 QTLs. More than half (44 QTLs = 59.45%) showed positive additive effects for fiber and yield traits. Five QTL clusters were identified, with three in the At, comprised of thirteen QTLs, and two in the Dt comprised of seven QTLs. The ILs developed in this study and the identified QTLs will facilitate further molecular breeding for improvement of Upland cotton in terms of higher yield with enhanced fiber quality.

Phosphorus (P) is one of the essential macronutrients for rice. In this study, we used 120 rice backcross recombinant inbred lines (BRILs) derived from a cross indica cv. Changhui 891 and japonica cv. 02428. To elucidate the genetic control of P deficiency tolerance in rice, we have used high quality SNPs bin markers to identify some important loci underlying phosphorus deficiency. The bin map was generated which includes 3057 bins covering distance of 1266.5 cM with an average of 0.41 cM between markers. Based on this map, 50 loci, including four novel loci, qSL-3, qRL-11, qSDW-1, qRDW-1 with phenotypic variance 23.26%, 12.06%, 9.89% associated with P deficiency-related seedling traits were identified. No significant QTLs was found for root length under P+, shoot fresh weight P− and root length, shoot fresh weight for P+, P− and their ratio respectively. Root fresh weight, and root dry weight were strongly correlated to each other, and QTLs for these variables were located on the same chromosome 1 at the same region. Notably, 3 pleiotropic regions is the pioneer of our study, and these regions would facilitate map-based cloning to expedite the MAS selection for developing low phosphorous tolerant varieties. This study not only improves our knowledge about molecular processes associated with P deficiency, but also provides useful information to understand the genetic architecture of low phosphorous tolerance.

The experiment was conducted for estimation of the heterosis in F1 hybrids in wheat genotypes. The research was conducted at the experimental field of Seed Production Development Centre, Sindh Agriculture University Tandojam during Rabi growing season 2019-20. The experiment was laid-out in randomized complete block design (RCBD) using three replications. The performance of parents and their hybrids, and heterotic effects were measured in various aspects like earliness characters (days taken to 75% heading, days taken to 75% maturity), morphological and yield traits like plant height, tillers plant-1, yield plant-1, and a physiology related trait; relative water content. The study consisted of six varieties and their six F1 hybrids. The parents used were TD-1, Benazir-2013, TJ-83, Hamal, Imdad-2005, Kiran-95 and their crosses were as TD-1 × Hamal, TD-1 × Benazir-2013, Benazir-2013 × TD-1, TJ-83 × Benazir-2013, TJ-83 × Imdad, Kiran-95 ×Benazir-2013. Results revealed that all the parents and hybrids were highly significant for all the parameters studied at P<0.01 level. The F1 hybrids Benazir-2013 × TD-1, TD-1 × Benazir-2013, TD-1 × Hamal and Kiran -95 × Benazir-2013 had showed better response in mid parent heterosis and heterobeltiosis for most of the traits except plant height. On the basis of current findings, it could be concluded that these cross combinations may be used in bread wheat for yield improvement