Analysis of Genetic Regions Related to Field Grain Number per Spike From Chinese Wheat Founder Parent Linfen 5064

Wheat founder parents have been important in the development of new wheat cultivars. Understanding the effects of specific genome regions on yield-related traits in founder variety derivatives can enable more efficient use of these genetic resources through molecular breeding. In this study, the genetic regions related to field grain number per spike (GNS) from the founder parent Linfen 5064 were analyzed using a doubled haploid (DH) population developed from a cross between Linfen 5064 and Nongda 3338. Quantitative trait loci (QTL) for five spike-related traits over nine experimental locations/years were identified, namely, total spikelet number per spike (TSS), base sterile spikelet number per spike (BSSS), top sterile spikelet number per spike (TSSS), fertile spikelet number per spike (FSS), and GNS. A total of 13 stable QTL explaining 3.91–19.51% of the phenotypic variation were found. The effect of six of these QTL, Qtss.saw-2B.1, Qtss.saw-2B.2, Qtss.saw-3B, Qfss.saw-2B.2, Qbsss.saw-5A.1, and Qgns.saw-1A, were verified by another DH population (Linfen 5064/Jinmai 47), which showed extreme significance (P < 0.05) in more than three environments. No homologs of reported grain number-related from grass species were found in the physical regions of Qtss.saw-2B.1 and Qtss.saw-3B, that indicating both of them are novel QTL, or possess novel-related genes. The positive alleles of Qtss.saw-2B.2 from Linfen 5064 have the larger effect on TSS (3.30%, 0.62) and have 66.89% in Chinese cultivars under long-term artificial selection. This study revealed three key regions for GNS in Linfen 5064 and provides insights into molecular marker-assisted breeding.

Effects of Ethyl methanesulfonate (EMS) on Seedling and Yield Contributing Traits in Basmati Rice

Increasing genetic diversity in crop plants has been used for chemical mutagenesis. Through the application of various mutagenic agents, over 430 new varieties have been derived as rice mutants (Oryza sativa L.) Chemical mutagens such as ethyl methane sulphonate (EMS), diepoxybutane derivative (DEB), sodium azide, and gamma ray, x-ray, and quick neutron irradiation have been commonly used to induce a large number of functional variations in rice and others crops. Among chemical mutagens, ethyl methane sulfonate (EMS) is the alkylating agent most widely used in plants because it induces nucleotide substitutions to be extremely frequent, as detected in various genomes. In this study, seeds of potential genotype of the popular variety, (Oryza sativa L. Super Basmati variety) were treated with EMS at concentrations of 0.25%, 0.50%, 0.75%, 1% and 1.5%. Various measurements on the M1 generation determined EMS sensitivity. As concentration of applied EMS increased, will decrease in germination, shoot length, root length, plant height, productive tillers, Panicle Length, Total Spikelet, sterile spikelet and fertility under field conditions were observed in M1 generation as compared to the non-treatment control. Emergence, shoot length, root length, plant height, productive tillers, Panicle Length, Total Spikelet, sterile spikelet and fertility also decreased with increases in EMS mutagenesis in an approximately linear fashion. The LD50 values were observed based on growth reduction of seedlings after EMS treatment with 0.25% and 0.50% on the rice variety (Oryza sativa L. spp.).

Growth and Yield Performance of Six Aman Rice Varieties of Bangladesh

A field experiment was conducted with six rice varieties to determine their growth and yield performance. The experiment was laid out in a randomized complete block design (RCBD) with four replications. All the growth and yield contributing attributes varied significantly among the six rice varieties. The results revealed that in all rice varieties maximum growth performance observed at 58-68 Days after transplanting and maximum dry matter production was observed at 68 days after transplanting. Maximum number of filled spikelet observed in Binadhan-17 (164.89/ penical) and that was significantly different from other varieties. Percent of sterile spikelet was highest in BRRI dhan39 (12.9%) and that was statistically similar with Binadhan-16 (11.96%) and BRRI dhan33 (12.36%). Maximum 1000-seed weight was observed in Binadhan-17 (27.25 g). Highest grain yield was obtained from Binadhan-17 (6.13 t/h) that was significantly different from other varieties. Lowest grain yield observed in BRRI dhan39 (4.49 t/h) that was statistically similar to BRRI dhan33 (4.57 t/h) and Binadhan-7 (4.86 t/h).

Sterile spikelets assimilate carbon in sorghum and related grasses

ABSTRACTSorghum and its relatives in the grass tribe Andropogoneae bear their flowers in pairs of spikelets, in which one spikelet (seed-bearing, or SS) of the pair produces a seed and the other is sterile or male (staminate). This division of function does not occur in other major cereals such as wheat or rice. Additionally, one bract of the seed-bearing spikelet often produces a long extension, the awn, which is in the same position as but independently derived from that of wheat and rice. The function of the sterile spikelet is unknown and that of the awn has not been tested in Andropogoneae. We used radioactive and stable isotopes of carbon, as well as RNA-seq of metabolically important enzymes to show that the sterile spikelet assimilates carbon, which is translocated to the largely heterotrophic SS, thereby functioning as a nurse tissue. The awn shows no evidence of photosynthesis. These results apply to distantly related species of Andropogoneae. Thus, the sterile spikelet, but not the awn, could affect yield in the cultivated species and fitness in the wild ones.

Effect of Urea Super Granule on Growth and Yield of Wheat

A field experiment was carried out at Agronomy Field, Bangladesh Agricultural University (BAU), Mymensingh during the period from November 2009 to March 2010 with a view to finding out the effect of appropriate dose of USG on growth and yield of wheat. Six levels of nitrogen (T0, T1, T2, T3, T4 and T5) were applied as treatments for growth and yield of wheat var. Bijoy for this study. Among the application of USG, treatment T5 produced the superior results on morpho-physiological and growth characters of wheat except number of non sterile spikelet where USG treatment T2 performs the best (1.82). As results, T5 produced the highest plant height (95.77 cm), number of total tiller hill-1 (4.96), no. of effective tiller (4.13), no of non effective tiller (1.00), number of total spikelet (20.22), no of spikelet spile-1 (10.92), sterile spieklet (18.70), no of grains spike-1 (46.27), 1000-grain yield (51.39 g), grain yield (2.42 t ha-1) and straw yield (4.06 tha-1).DOI: http://dx.doi.org/10.3329/jesnr.v4i2.10164 J. Environ. Sci. & Natural Resources, 4(2): 143-146, 2011