Characterization of early maturing elite genotypes based on MTSI and MGIDI indexes:an illustration in upland cotton(Gossypium hirsutum L.)

Background Globally,the cultivation of cotton is constrained by its tendency for extended periods of growth.Early maturity plays a potential role in rainfed-based multiple cropping system especially in the current era of climate change.In the current study,a set of 20 diverse Gossypium hirsutum genotypes were evaluated in two crop seasons with three planting densities and assessed for 11 morphological traits related to early maturity.The study aimed to identify genotype(s)that mature rapidly and accomplish well under diverse environmental conditions based on the two robust multivariate techniques called multi-trait stability index(MTSI)and multi-trait genotype-ideotype distance index(MGIDI).Results MTSI analysis revealed that out of the 20 genotypes,three genotypes,viz.,NNDC-30,A-2,and S-32 accomplished well in terms of early maturity traits in two seasons.Furthermore,three genotypes were selected using MGIDI method for each planting densities with a selection intensity of 15%.The strengths and weaknesses of the genotypes selected based on MGIDI method highlighted that the breeders could focus on developing early-maturing genotypes with specific traits such as days to first flower and boll opening.The selected genotypes exhibited positive genetic gains for traits related to earliness and a successful harvest during the first and second pickings.However,there were negative gains for traits related to flowering and boll opening.Conclusion The study identified three genotypes exhibiting early maturity and accomplished well under different planting densities.The multivariate methods(MTSI and MGIDI)serve as novel approaches for selecting desired genotypes in plant breeding programs,especially across various growing environments.These methods offer exclusive benefits and can easily construe and minimize multicollinearity issues.

Relationship Among Yield Components and Selection Criteria for Yield Improvement in Early Rapeseed (Brassica napus L.)

The objective of this study was to determine the relationship between seed yield and other important agronomic traits of early-maturing rapeseed as a rotation crop in a double-cropping rice area using Pearson＇s correlation coefficient as well as to estimate direct and indirect effects of specific yield component traits on seed yield via path analysis. Nineteen rapeseed genotypes were grown at ten environments in South China during 2008-2009 and 12 characters were evaluated. Analysis of variance showed that environment had a significant impact on all characters. For most characters the genotype by environment interaction was weak and not statistically significant. Simple correlation analysis indicated that the number of primary branches （PB）, number of pods on the main raceme （PR）, and number of seeds per pod made significant contributions to seed yield per plant （SYP）, while 1 000-seed weight was negatively correlated with SYP （r=-0.485, P0.05）. Furthermore, number of pods per plant （PP）, PB, and PR had the greatest direct effects on SYP. In addition, PP and PB were the best indicators to predict seed yield in stepwise regression analysis. Finally, yield component differences between early- and medium-maturity varieties were compared; this showed that to improve the seed yield of early varieties, more emphasis should be given to increase PP, PB, and PR, and reduce plant height and shortening of growth duration in breeding practice.

Development of a New Foxtail Millet Germplasm with Super Early Maturity and High Iron Content

Super Early Maturation No.2 is a new foxtail millet germplasm developed by using the targeted-character-gene-bankbreeding method. It has several outstanding characteristics. （1） Super early maturity. It can normally mature in Bashang, Hebei Province, China, where the altitude is around 1400 meters, and it needs 1 650℃ of effective accumulated temperature in the growing period. （2） Millet is rich in iron. The iron content of the millet of Super Early Maturation No.2 is 54.10 mg·kg^-1, which is 62.0% higher than the average iron content of the foxtail millet varieties in China. （3） High crude fat content. Its crude fat content is 6.24%, which is 54.1% higher than the average content of foxtail millet varieties in China. （4） High crude protein content. The average of the crude protein content of all the foxtail millet varieties in China is 12.71%, only 5% varieties surpass 14%, however, the crude protein content of Super Early Maturation No.2 is 14.36%, which is rare in improved varieties of foxtail millet in China. （5） Overall characteristics are good.

Biochemical Genetic Mechanism and QTLs of Early Maturing without Yield Loss in Short-season Upland Cotton(Gossypium hirsutum L.)

The short season cotton(SSC) was important Upland plant ecotype(Gossypium hirsutum L.).The growth of SSC was very short that is 105 ～ 110 days(after planting). SSC could increase

In Vitro Propagation Potential via Somatic Embryogenesis of the Two Maturing Early Cultivars of European Chestnut (Castanea sativa Mill.)

Turkey ranks the third in the production of chestnuts in the world having an important place both in domestic and global markets. However, the chestnut production and the number of trees have been diminishing in recent years. Therefore, in vitro propagation of the chestnut, in addition to the classical propagation techniques, should be applied. Especially the propogation of the early maturing cultivars and production of the quality chestnuts will provide a better income to the producer. Here, somatic embryo production and regeneration from the immature cotyledons of the early maturing cultivars of the European chestnut (Castanea sativa Mill), Haciibis and Karamehmet, were studied using the somatic embryogenesis, one of the in vitro propagation techniques. To induce the somatic embryogenesis, 168 different combinations were applied to both cultivars. The somatic embryogenesis rate in Haciibis cultivar, in which the interactions were observed among the applications, was found to be 9.9% while it was 11.1% for the Karamehmet cultivar. Dessication, cold treatment, gibberellic acid (GA3) and benzyladenine (BA) + naphthaleneacetic acid (NAA) applications were performed on the regeneration of the somatic embryos, and 40% conversion to plant was obtained with desiccation together with BA + NAA supplementation to the medium.

The Main Characteristics of Early Maturing Kiwifroit Variety "Fengyue" and Its Cultivating Techniques for High Yield and Good Quality

The new kiwifruit variety 'Fengyue' has bigger,avg.90g,max.127.8g fruit with beautiful appearance and good storage tolerance.The fruit is fine and tender in pulp texture with a thick sweet taste and rich refreshing aroma in addition to over 15% soluble solids content.This variety matures in September,Changsha,and has a high fruit setting percentage.Fruiters should pay great attention to fertilizer or water management,pruning,and flower or fruit thinning in cultivating'Fengyue

An early maturing rice variety of high quality—Zhefu 218

Early maturing rice variety of high quality "Zhefu 218" was developed by prof XIA Yingwu, Zhejiang Agricultural University, Hangzhou, China. The growth period of the new rice variety is 106 d and its average yield is about 5.25-7.08 t / ha. It has the speciality of early-maturing combined with good quality. Not only the grains of "Zhefu 218" are of excellent cooking, but also of nutritive quality. The flavour of the cooked rice of"Zhefu 218" is considerably better than those of the ordinary rice cultivars here.

Spectral narratives of microstructural restyling and their controls on hydrocarbon generation potential from coal

The low to medium-rank Tertiary coals from Meghalaya,India,are explored for the first time for their comprehensive micro-structural characterization using the FTIR and Raman spectroscopy.Further,results from these coals are compared with the Permian medium and high-rank coals to understand the microstructural restyling during coalification and its controls on hydrocarbon generation.The coal samples are grouped based on the mean random vitrinite reflectance values to record the transformations in spectral attributes with increasing coal rank.The aliphatic carbon and the apparent aromaticity respond sharply to the first coalification jump(R:0.50%)during low to medium-rank transition and anchizonal metamorphism of the high-rank coals.Moreover,the Raman band intensity ratio changes during the first coalification jump but remains invari-able in the medium-rank coals and turns subtle again during the onset of pregraphitization in high-rank coals,revealing a polynomial trend with the coal metamorphism.The Rock-Eval hydrogen index and genetic potential also decline sharply at the first coalification jump.Besides,an attempt to comprehend the coal microstructural controls on the hydrocarbon poten-tial reveals that the Tertiary coals comprise highly reactive aliphatic functionalities in the type I-S kerogen,along with the low paleotemperature(74.59-112.28℃)may signify their potential to generate early-mature hydrocarbons.However,the presence of type II-II admixed kerogen,a lesser abundance of reactive moieties,and overall moderate paleotemperature(91.93-142.52℃)of the Permian medium-rank coals may imply their mixed hydrocarbon potential.Meanwhile,anchizonal metamorphism,polycondensed aromatic microstructure,and high values of paleotemperature(~334.25 to~366.79℃)of the high-rank coals indicate a negligible potential of producing any hydrocarbons.

Breeding and Cultivation Technique of New Watermelon Variety Jingang No.2 Heimeiren

Jingang No. 2 Heimeiren is a new early-maturing watermelon vadety in small to middle size with strong disease resistance bred with ZK09 as female par- ant and ZS05 as male parent. As to whole growth period, the spring crop grows for 90-110 d, the autumn crop grows for 70-80 d, and the fruit development period is 27-29 d. The fruit is oblong with a fruit shape index of 1.5, the average single fruit weight is 3.18 kg, and the fruit surface is smooth in deep green color with dark green netted stripes. The fruit flesh is bright red, crisp, with a soluble solid content in the center of 11.5%. The fruit has a peel thickness of 1.0 cm with high storage tolerance, good appearance and good commodity. The variety is suitable for Guangxi, Guangdong and Halnan.

GhAP1-D3 positively regulates flowering time and early maturity with no yield and fiber quality penalties in upland cotton

Flowering time(FTi)is a major factor determining how quickly cotton plants reach maturity.Early maturity greatly affects lint yield and fiber quality and is crucial for mechanical harvesting of cotton in northwestern China.Yet,few quantitative trait loci(QTLs)or genes regulating early maturity have been reported in cotton,and the underlying regulatory mechanisms are largely unknown.In this study,we characterized 152,68,and 101 loci that were significantly associated with the three key early maturity traits—FTi,flower and boll period(FBP)and whole growth period(WGP),respectively,via four genome-wide association study methods in upland cotton(Gossypium hirsutum).We focused on one major early maturity-related genomic region containing three single nucleotide polymorphisms on chromosome D03,and determined that GhAP1-D3,a gene homologous to Arabidopsis thaliana APETALA1(AP1),is the causal locus in this region.Transgenic plants overexpressing GhAP1-D3 showed significantly early flowering and early maturity without penalties for yield and fiber quality compared to wild-type(WT)plants.By contrast,the mutant lines of GhAP1-D3 generated by genome editing displayed markedly later flowering than the WT.GhAP1-D3 interacted with GhSOC1(SUPPRESSOR OF OVEREXPRESSION OF CONSTANS 1),a pivotal regulator of FTi,both in vitro and in vivo.Changes in GhAP1-D3 transcript levels clearly affected the expression of multiple key flowering regulatory genes.Additionally,DNA hypomethylation and high levels of H3K9ac affected strong expression of GhAP1-D3 in early-maturing cotton cultivars.We propose that epigenetic modifications modulate GhAP1-D3 expression to positively regulate FTi in cotton through interaction of the encoded GhAP1 with GhSOC1 and affecting the transcription of multiple flowering-related genes.These findings may also lay a foundation for breeding early-maturing cotton varieties in the future.

Recent Advances,Problems and Outlooks in Rapeseed(Brassica napus L.)Breeding in China

As a big rapeseed （Brassica napus L.） producing and consuming country, China provides more and more rapeseea oil year by year. With the development of demand for rapeseed and import of edible oil, rapeseed breeding and production is fac- ing a great challenge. New situation has proposed higher requirements to yield, oil quality and safety, etc. In the review, some aspects about rapeseed breeding in China were reported, including breeding of high-oil content rapeseed, breeding of extremely early-maturing rapeseed, development of mechanization and development of chemical emasculation. Some prospects and expec- tations were also proposed.

GmNF-YC4 delays soybean flowering and maturation by directly repressing GmFT2a and GmFT5a expression

Flowering time and growth period are key agronomic traits which directly affect soybean(Glycine max(L.)Merr.)adaptation to diverse latitudes and farming systems.The FLOWERING LOCUS T(FT)homologs GmFT2a and GmFT5a integrate multiple flowering regulation pathways and significantly advance flowering and maturity in soybean.Pinpointing the genes responsible for regulating GmFT2a and GmFT5a will improve our understanding of the molecular mechanisms governing growth period in soybean.In this study,we identified the Nuclear Factor Y-C(NFY-C)protein GmNF-YC4 as a novel flowering suppressor in soybean under long-day(LD)conditions.GmNF-YC4 delays flowering and maturation by directly repressing the expression of GmFT2a and GmFT5a.In addition,we found that a strong selective sweep event occurred in the chromosomal region harboring the GmNF-YC4 gene during soybean domestication.The GmNF-YC4Hap3 allele was mainly found in wild soybean(Glycine soja Siebold&Zucc.)and has been eliminated from G.max landraces and improved cultivars,which predominantly contain the GmNF-YC4Hap1 allele.Furthermore,the Gmnf-yc4 mutants displayed notably accelerated flowering and maturation under LD conditions.These alleles may prove to be valuable genetic resources for enhancing soybean adaptability to higher latitudes.