Table_8_Understanding Heterosis, Genetic Effects, and Genome Wide Associations for Forage Quantity and Quality Traits in Multi-Cut Pearl Millet.XLSX

Pearl millet is an important food and fodder crop cultivated in the arid and semi-arid regions of Africa and Asia, and is now expanding to other regions for forage purpose. This study was conducted to better understand the forage quantity and quality traits to enhance the feed value of this crop. Two sets of pearl millet hybrids (80 single cross hybrids in Set-I and 50 top cross hybrids in Set-II) along with their parents evaluated multi-locationally for the forage-linked traits under multi-cut (two cuts) system revealed significant variability for the forage traits in the hybrids and parents. The mean better parent heterosis (BPH) for total dry forage yield (TDFY) was 136% across all the single cross hybrids and 57% across all the top cross hybrids. The mean BPH for in vitro organic matter digestibility (IVOMD) varied from −11 to 7% in the single cross hybrids and −13 to 11% in the top cross hybrids across cuts. The findings of TDFY and IVOMD heterosis in these sets indicated the potential of improvement of the hybrid cultivars for forage quantity and quality in forage pearl millet. The parental lines single cross parent (SCP)-L02, SCP-L06, and top cross parent (TCP)-T08 found superior in the forage quantity and quality traits can be utilized in the future breeding programs. Most of the forage traits were found to be controlled by using the non-additive gene action. A diverse panel of 105 forage-type hybrid parents (Set-III) genotyped following genotyping by sequencing (GBS) and phenotyped for crude protein (CP) and IVOMD under multi-cuts for 2 years identified one stable significant single nucleotide polymorphism (SNP) on LG4 for CP, and nine SNPs for IVOMD distributed across all the linkage groups except on LG2. The identified loci, once validated, then could be used for the forage quality traits improvement in pearl millet through marker-assisted selection.

珍珠粟（Pearl millet）是重要的粮食与饲料作物，主要栽培于非洲和亚洲的干旱半干旱区域，当前为满足饲料用途已向其他地区推广。本研究旨在深入解析其饲料产量与品质性状，以提升该作物的饲料利用价值。本研究针对两套珍珠粟杂交群体开展多环境评价：第一套（Set-I）包含80个单交杂交种，第二套（Set-II）包含50个顶交杂交种，连同其亲本在内，采用两刈割体系对饲料相关性状进行测试，结果显示杂交种及亲本的饲料性状均存在显著遗传变异。总干饲料产量（total dry forage yield, TDFY）的平均超亲优势（better parent heterosis, BPH）在所有单交杂交种中达136%，在所有顶交杂交种中为57%；体外有机物消化率（in vitro organic matter digestibility, IVOMD）的平均超亲优势在单交杂交种中介于-11%至7%之间，在不同刈割批次的顶交杂交种中介于-13%至11%之间。上述总干饲料产量与体外有机物消化率的超亲优势结果表明，饲用珍珠粟的饲料产量与品质杂交品种具备遗传改良潜力。本研究筛选出的单交亲本（single cross parent, SCP）-L02、SCP-L06以及顶交亲本（top cross parent, TCP）-T08在饲料产量与品质性状上表现优异，可应用于后续育种项目。多数饲料性状由非加性基因效应调控。此外，本研究构建了包含105份饲用型杂交亲本的多样性群体（Set-III），通过测序分型（genotyping by sequencing, GBS）进行基因型鉴定，并在2年多刈割环境下对粗蛋白（crude protein, CP）含量与体外有机物消化率进行表型鉴定，结果在LG4连锁群上检测到1个与粗蛋白含量显著相关的稳定单核苷酸多态性（single nucleotide polymorphism, SNP），另有9个与体外有机物消化率相关的单核苷酸多态性，分布于除LG2外的所有连锁群。上述鉴定得到的位点经验证后，可通过标记辅助选择（marker-assisted selection）用于珍珠粟饲料品质性状的遗传改良。