QTL Analysis of Agronomic Traits in Soybean

[Objective]The aim was to analyze QTL of agronomic traits in soybean and provide reference for a discussion on soybean genetic mechanism and genetic breeding. [Method]The composite interval mapping method was used for QTL location and genetic effects analysis on 5 quantitative traits including protein content,fat content,yield,100-grain weight and growth period. [Result]The control of these traits 4,4,1,2,5,a total of 16 QTL loci was detected. The genetic contribution rate was in 7.4%-33.7%,among which,a large main-effect QTL of the genetic contribution rate were located in linkage group I Satt562-Sat_219,Sat_219-Satt496,Sat_219-Satt496 interval of the three control protein content QTL sites,their genetic contribution rates were 29.15%,33.7 % and 31.67% respectively,all from the female parent Hefeng 25 plus minor gene; still in O linkage group Satt477-Satt331,Satt331-Satt153 interval of two control growing period QTL loci,their genetic contribution rates were up to 24.69% and 24.96%,also from the female parent Hefeng 25 plus minor gene. In addition,six QTL sites from M linkage group Satt175 （protein）,A1 linkage group Satt684 （oil）,F linkage group Satt348 （oil）,J linkage group Sat_412 （oil）,C1 linkage group Sat_416 （100-grain weight） and C1 linkage group Sat_416 （growth period） marks only 0.01 cm were detected. [Conclusion]QTL sites which had effects on the 5 important agronomic traits in soybean were located.

Relation Analysis of Several Agronomic Traits and Single Plant Lint Yield in Upland Cotton with High Quality

[ Objective] The purpose was to study the correlation between main agronomic traits and single plant lint yield in upland cotton with high quality. [ Method] Twenty-four upland cotton lines with high quality were analyzed for single plant lint yield and 10 agronomic traits in a randomized, complete block at the agriculture experimental station of JXAU, Nanchang, China in 2007. They were divided into three types （ high, medium, low yield） based on single plant lint yield by Ward＇s method. A total of 11 traits of three types were compared. Correlation a- nalysis and stepwise regression analysis of 10 agronomic traits to single plant lint yield were carried out. [ Result] There existed statistically sig- nificant difference in bolls per plant, ~int percentage, lint index, fruit node numbers, growth period for three yield types. The high yield type ex- hibited the highest bolls per plant, lint percentage and lint index, the lowest fruit node numbers and the shortest growth period. Bolls per plant, boll weight and single plant lint yield were significantly and positively correlated. Fruit node numbers and single plant lint yield were significantly and negatively correlated. Bolls per plant, boll weight, and fruiting position number were the most important factors influencing single plant lint yield of upland cotton lines with high quality. [ Conclusion ] The results will have certain significance for the development of upland cotton variety with high quality.

RITSD Analysis of the Agronomic Traits of Somaclonal in Rice

[Objective]The aim was to study the sensitive response characteristics of the main agronomic traits of somaclonal and the variation of sensitive response of the lines of somaclonal to sowing date. [Method]The RITSD changing of agronomic traits was studied by using 24 rice somaclonal and its donor parent under two sowing dates. [Result]The average values of RITSD were higher （over one） for the traits of pant height （PH）,density of spikelets （DS）,filled spikelets per panicle （FSP）,spikelets per panicle （SP） and grain weight per plant （GWP）,but lower for days of sowing to heading （DSH）,effective panicles （EP）,panicle length （PL）,seed setting rate （SS） and 1 000-grain weight （1 000-GW）. These showed that PH,DS,FSP,SP and GWP were easily affected by sowing date and tended to higher with the later sowing; the RITSD of somaclonal changed with the agronomic traits. The frequency of RITSD＇ variation of DSH and PH was higher than that of PL. The RITSD＇ value of EP,PL,DS,FSP,SP and SS became higher,and higher or lower for DSH and GWP in different somaclonal; compared with the donor,20 of 24 was significantly different,and the frequency of RITSD variation was over 83. 3%,however,RITSD of the most lines （75%） changed only for 1-2 characters; cluster analysis showed that the RITSD of agronomic traits belonged to different combinations of somaclonal in rice. [Conclusion]the study had provided a theoretical basis for the screening and using of the somaclonal.

Improvement for Agronomic Traits of Partial Waxy Wheat by Combination of Backcrossing with a PCR-based DNA Marker

To improve agronomic traits of partial waxy wheat, crossing between Chinese Baihuomai and wheat cultivars PH85-16, Jinan 17, and Yannong 15 was performed. The progeny plants were further backcrossed to these cultivars as recurrent parents for five generations. To get homozygous plants with the null allele at the Wx-D1 locus, self-pollination was carried out in the BC5F1 generation. Through another three generations, 6 partial waxy wheat lines were obtained, which had similar agronomic performance as their recurrent parents and carried the null allele at the Wx-D1 locus. In each generation, the Wx-D1 locus was identified by a PCR-based DNA marker and the agronomic traits were examined in progeny plants. The results from this study indicate that the use of backcrossing with a PCR-based DNA marker was useful in waxy wheat breeding. These partial waxy wheat lines can be used in field production.

Correlation and Principal Component Analysis on Main Agronomic Traits of New Waxy Corn Varieties

[Objective] This study was conducted to provide certain theoretical reference for the comprehensive evaluation and breeding of new fresh waxy corn vari- eties. [Method] With 5 good fresh waxy corn varieties as experimental materials, correlation analysis and principal component anatysis were performed on 13 agronomic traits, i.e., plant height, ear position, ear weight, ear diameter, axis diameter, ear length, bald tip length, ear row number, number of grains per row, 100-kernel weight, fresh ear yield, tassel length, and tassel branch number. [Result] The principal component analysis performed to the 13 agronomic traits showed that the first three principal components, i.e., the fresh ear yield factors, the tassel factors and the bald top factors, had an accumulative contribution rate over 87.2767%, and could basically represent the genetic information represented by the 13 traits. The first principal component is the main index for the selection and evaluation of good corn varieties which should have large ear, large ear diameter but small axis diameter, i.e., longer grains, larger number of grains per ear, higher, 100-grain weight and higher plant height. As to the second principal component, the plants of fresh corn varieties are best to have longer tassel and not too many branches, and under the premise of ensuring enough pollen for the female spike, the varieties with fewer tassel branches shoud be selected as far as possible. From the point of the third principal component, bald tip length affects the marketing quality of fresh corn, and during fariety evaluation and breeding, the bald top length should be control at the Iowest standard. [Conclusion] The fresh ear yield of corn is in close positive correlation with ear weight, 100-grain weight, ear diameter, number of grains per row and ear length, and plant height also affects fresh ear yield.

Identification of Faba Bean(Vicia faba L.)Germplasm Resources in Hubei Province and Evaluation on Their Main Agronomic Traits

Through field observation and lab analysis, 13 agronomic traits, including plant height and effective branching number per plant, etc., of 207 faba bean （Vicia faba L.） germplasms saved in Crop Middle-term Genebank of Hubei Province were evaluated, moreover, the identification on the disease resistance and the quality was carried out on parts of germplasm resources. The results showed that the faba beangermplasm resources in Hubei Province were abundant, the variation range of agronomic traits like the growth period, plant height and 100-bean weight, etc., was great, and the range of choice was wide. In the aspect of quality, there were 9 germplasms withthe content of crude protein higher than 30%, and the variation range of amylose content in total starch was large, which provided excellent sources of parents for breedinq hi.qh-quality faba bean varieties in Hubei Province.

Research on the Agronomic,Quality Traits and the Corresponding Background Genes Distribution of Wheat Germplasm Ningchun 4 and Its Parents

[Objective] The aim of this study was to observe the agronomic,yield and quality traits of Ningchun 4 and its parents under the same environmental conditions,as well as to carry out molecular detection on the background genes distribution of the corresponding traits.[Method]Ningchun 4 and its parents Sonora 64,Hongtu,Abbondanza,Quality were used as materials to detect the agronomic and quality traits,as well as to analyze the genetic variation laws by molecular determination method.[Result]Ningchun 4 had inherited the advantages of bigger spike,red and hard grain from Sonora 64 and higher 1 000-grain weight from Hongtu.However,it had also inherited the disadvantages of late-maturing from Sonora 64 and lower tillering ability from Hongtu;the grain quality of Ningchun 4 was slightly lower than the Sonora 64;Ningchun 4 had high quality subunit of 5＋10,which had good dough rheological properties.[Conclusion]Ningchun 4 had inherited the long photoperiod characteristics and no-resistant to slow-leaf rusting and stripe rust characteristics from Hongtu and low PPO activity,high yellow pigments content from parents.

Analysis on the Combining Ability and Heritability of Main Agronomic Traits of Hybrid Glutinous Sorghum

Using 3 sterile lines and 12 restorer of glutinous sorghum as experimental materials,36 hybrid combinations（3×12 NCⅡ） were designed to analyze the combining ability and heritability of six main agronomic traits,including plant height,panicle length,growth period,1 000-grain weight,per panicle grains and per panicle grain weight.The results showed that except per panicle grain number all other five agronomic traits have remarkable or extremely remarkable general combining ability and specific combining ability.Six agronomic traits were found to be control by additive genetic effect.Most of these agronomic traits are more easily influenced by restorers than sterile lines,suggesting that more attention should be paid to select restores in hybrid glutinous sorghum breeding.The narrow-sense heritability of these agronomic traits were in order growth period plant height per panicle grain weight panicle length 1 000-grain weight per panicle grains.

Traits Analysis and Evaluation on Several Alfalfa Varieties

The agronomic and qualitative traits of 17 alfalfa varieties were analyzed in field and lab from 2006 to 2008, and these traits were evaluated by principal component analysis and cluster analysis. A total of 10 main traits were classified as five factors： growth factor, quality factor, stem and leaf factors, plant factor and yield factor. These five factors and their correlation were selected for breeding. These 17 varieties can be divided into five clusters. The domestic varieties have better agronomic traits, while the introduced ones have better qualitative traits.

Changes in Agronomic Traits of Indica Hybrid Rice during Genetic Improvement

[Objective]The aim was to elucidate the changes of agronomical traits of indica hybrid rice during its genetic improvement.[Method]23 typical indica hybrid combinations cultivated in the middle and lower reaches of Yangtze River during the last 30 years were selected as experimental materials.All the hybrid rice combinations were grown in the same field;and then yield and morphological characters of single plant were compared;correlation and path analyses among agronomic characteristics were also conducted.[Result]During the 30 years of genetic improvement,the effective panicle number per plant was progressively decreased,which caused the decrease of grain yield and biomass per plant of hybrid rice combinations in spite of the slightly increased plant height,1 000-grain weight and number of grains per panicle.Although the transformation percentage of the matter in stem and sheath decreased after flowering,leave photosynthetic capacity after flowering was increased as panicle weight.Correlation and path analysis showed that although both biomass per plant and number of grains per panicle were significantly correlated with grain yield per plant,biomass per plant acted as the key factor affecting yield per plant.[Conclusion]It was suggested that in rice high yield cultivation,panicle number was as important as large panicle,and tillering ability should not be neglected in breeding.

Effects on Agronomic Traits of M_1 by Pollen of Upland Cotton Irradiated by ^(60)Co-γ Ray

[Objective] The aim was to provide reference for research on radiation and breeding of cotton pollen through irradiating common ripe pollen grain of upland cotton by 60Co-γ Ray of varied doses. [Method] Ripe pollen grains of upland cotton were irradiated by 60Co-γ Ray with doses of 5, 10, 15, and 20 Gy, respectively, to learn radiation effect and select appropriate dose. [Result] Most properties of M1 obviously showed variation when dose was over 10 Gy; vitality, growth, and fertility were greatly inhibited when dose was 15 Gy which was almost semi-lethal concentration, and variation species were richest at the same time, which provided materi- als for practical breeding. [Conclusion] 60Co-γ Ray of 15 Gy is more suitable for mutagenesis research on ripe pollen grains of upland cotton.

Effects of Genotype and Planting Density on Agronomic Traits and Storage Root of Sweetpotato

The effects ol different genotypes and planting densities on main agronomic traits, storage root traits and yield were studied with 6 high-quality sweetpotato varieties as study objects by 2-factor completely random design. The results showed that there were significant differences in stem diameter, length of the longest vine and top/root （T/R） between different genotypes, T/R differed significantly under dif- ferent planting densities, and number of basal branches decreased with planting density increasing. Genotype and genotype x density showed significant or very sig- nificant effects on fresh root yield per plant, dry matter content and fresh root yield per hectare, fresh root yield per plant gradually decreased with planting density in- creasing, while fresh root yield per hectare increased with planting density increas- ing. Numbers of storage roots in different sizes of the 6 sweetpotato cultivars all exhibited an order of number of large-sized storage roots〈number of medium-sized storage roots〈small-sized storage root; and there were very significant differences in ratio of large-sized storage roots between different genotypes. The number of large- sized storage roots, ratio of large-sized storage roots and number of commercial storage roots deceased with planting density increasing, while there were no signifi- cant differences in number of medium-sized storage roots, number of small-sized storage roots, ratio of medium-sized storage roots and ratio of small-sized storage roots between different densities. Correlation analysis showed that there was signifi- cant positive correlation between number of basal branches and fresh root yield per plant; dry matter content in storage roots was in significant positive correlation with stem diameter, and in significant negative correlation with length of the longest vine; fresh root yield per hectare was in significant positive correlation with fresh root yield per plant, and in very significant negative correlation with dry matter content; and ratio of large-sized storage roots was in very significant positive correlation with number of large-sized storage root and fresh root yield per plant, and in very sig- nificant negative correlation with ratio of medium-sized storage roots and ratio of small-sized storage roots. This experiment showed that under the planting density of 7.5×104 plants/hm2, the 6 sweetpotato cultivars all reached the highest numbers of commercial storage roots and fresh root yields per hectare.

Effects of Spraying Deltamethrin on Agronomic Traits and Yield of Soybean

At the seedling and beginning flowering stages,2.5% deltamethrin EC was sprayed to control the pests in summer soybean,and its effects on agronomic traits and yield of soybean were analyzed.The results showed that compared with the control,the plant height,branch number,effective pod number,grain number per plant,grain weight per plant,100-grain weight and yield of Qihuang 34 significantly increased by 9.3%,25.8%,15.8%,26.8%,33.2%,9.1% and 33.0%,respectively,while those of Qihuang 35 increased by 13.8%,10.0%,15.8%,16.9%,11.6%,6.0%and 16.9%,respectively;the noneffective pod number of Qihuang 34 and Qihuang35 significantly decreased by 18.5% and 38.7%,respectively.The spraying of 2.5%deltamethrin EC showed no significant effects on the other agronomic traits of the two cultivars.

A Study on the Effects of Oxygenation Irrigation on Some Growth Agronomic Traits of Super Rice Shenyou 9516

In the growing process of rice, roots need aerobic respiration. Oxygenation irrigation means oxygenation in accordance with the demand of crops for oxygen for their growth. This experiment designed three treatments： mechanical oxygenation, chemical oxygenation and conventional irrigation. The mechanical oxygenation group A was divided into 6 small treatment groups and the chemical oxygenation group B was divided into 3 small treatment groups. Each treatment group had 3 replications and the average was used for analysis. Some agronomic traits of the roots and the plants of super rice were examined. The result showed that the two oxygenation treatments significantly promoted the growth of the roots and the plants. In the me- chanical oxygenation group A4, the number of filled grain per panicle was 37.6% higher than that of the conventional treatment group, and the kilo-grain weight was 7.4% higher than that of the conventional treatment group. The study results provide a theoretical basis for the application of oxygenation irrigation to super rice.

Physical-chemical and Agronomical Analysis of a Leaf Color Mutant of Rice

[Objective] This study was to investigate the physical-chemical properties and the agronomical traits of a leaf color mutant K7231,so as to provide scientific basis for its use as breeding material.[Method]Before heading,the contents of chlorophyll and soluble sugar of leaf color mutant K7231 were measured,and its agronomic traits after mature were investigated.[Result]The contents of chlorophyll and soluble sugar of leaf color mutant K7231 before heading assumed a regular change law.Except the lower yield,K7231 performed similar agronomic traits compared with the CK.[Conclusion]This study provided scientific basis for the utilization of this mutant.

Genetic Analysis on Agronomic Traits of Doubled Haploid Population in Tobacco

[Objective] This study aimed to conduct genetic analysis on agronomic traits of doubled haploid population in tobacco. [Method] Main agronomic traits of DH population in tobacco were investigated, including plant height, effective number of leaves, lumbar leaf length, lumbar leaf width, intermodal distance and pericaulome length. Based on the estimation of skewness coefficient and kurtosis coefficient of Hongda x Hicks Broad Leaf populations, the number of gene pairs was calculated. [Result] The number of gene pairs controlling plant height （topping plant height and natural plant height） is 10.20 and 10.80, respectively; the number of gene pairs con- trolling leaf number （effective number of leaves and natural number of leaves） is 6.21 and 6.25, respectively; the number of gene pairs controlling pericaulome length, intermodal distance, lumbar leaf length and lumbar leaf width is 8.51, 15.30, 20.36 and 17.45, respectively. [Conclusion] This study revealed the characteristics of genetic variation of tobacco traits, which provided theoretical basis for the breeding of new varieties.

Mutation Classification and Genetic Diversity Analysis of Triticum aestivum ssp. yunnanense King Based on Agronomic Traits

[Objective] The present study was conducted to provide basis for researches on breeding new wheat varieties and conserving rare species in Yunnan Province.[Method] 29 materials of Triticum aestivum ssp.yunnanense King（Yunnan Hulled Wheat）were taken for the research on classification and genetic diversity analysis based on 14 agronomic traits.[Result] Yunnan hulled wheat A14 could be an unnamed white seed variety,and other 28 materials were divided into 10 named mutation types;Yunnan hulled wheat was rich in variability of agronomic traits,in which the coefficient of variance（CV）of sterile spikelet number was the largest（22.59%）,while the CV of earing period was the lowest（3.71%）;the diversity indexes of seven qualitative characters ranged from 1.55-2.04.Moreover,the 29 Yunnan hulled wheat could be divided into 3 clusters by the UPGMA analysis.However,Yunnan hulled wheat varieties originating from similar mutation types did not completely cluster together.The genetic relationship was relatively close among A13（YT-35）,A14（YT-36）and A21（YT-37）,but the faster genetic relationship was observed between them and other Yunnan hulled wheat varieties.[Conclusion] Yunnan hulled wheat had an extensive genetic diversity in agronomic traits.

Principal Component Analysis on Traits Related to Lodging Resistance of Plateau Japonica Rice

Objective] This study was conducted to investigate the main factors affect-ing the lodging resistance of plateau japonica rice. [Method] Twenty agronomic traits related to lodging resistance of plateau japonica rice were analyzed by principal component analysis and correlation analysis among 26 varieties/lines of plateau japonica rice. [Result] The lodging resistance of the 26 varieties/lines had great dif-ference among different agronomic traits. Plant height, and wal thickness of the 4th, 3rd and 2nd internodes under the panicle had the most important influence on lodging resistance, while the diameter of the 3rd, 2nd, 4th, 1st nodes under the panicle, length of the 4th and 3rd internodes under the panicle, wal thickness of the 1st internode under the panicle had less influence. The other nine agronomic traits of rice culm did not affect or indirectly affected lodging resistance through above-mentioned agro-nomic traits. Lodging resistance had significant correlations with plant height, length of the 4th and 3rd internodes under the panicle, wal thickness of the 1st, 2nd, 3rd and 4th internodes under the panicle and diameter of the 1st, 2nd, 3rd and 4th node sunder the panicle, had insignificant correlations with panicle length, panicle weight, length of the 1st and 2nd internodes under the panicle, diameter of the 1st, 2nd, 3rd and 4th internodes under the panicle, diameter of the 5th node under the panicle. [Conclu-sion] More attention should be paid to the main factors affecting lodging resistance in breeding to improve lodging resistance of plateau japonica rice.

Correlation Analysis on Main Agronomic Traits and Yield and Quality of Hybrid Cotton

ObjectiveThis study aimed to analyze the correlations of the main agronomic traits, yield and quality of hybrid cotton cultivars. MethodThe growth period, main agronomic traits, yield components, yield and quality of 13 hybrid cotton cultivars were compared, and the correlations of their main agronomic traits, yield components, yield and quality were analyzed. ResultThe growth period of the 13 cultivars was about 123 d, and all of them presented strong growth potential throughout the growth period. The ginned cotton yield shared an extremely significant positive correlation with the first fruiting branch position, plant height, number of fruiting branches, number of bolls per plant, number of bolls per hectare and seed cotton yield; the first fruiting branch position and micronaire value shared a significant positive correlation. Keza No.1 and Chunzamian No.1 had the lowest micronaire value, 4.5. The specific strength of all the cotton cultivars ranged from 27 cN/tex to 30 cN/tex, presenting significant difference. In addition, there was extremely significant difference in the ginned cotton yield among all the cotton cultivars. ConclusionThe study provides theoretical reference for the cultivation of high-yield hybrid cotton.

Quantitative Traits of Ion Beam Induced Mutagenesis in Triticum aestivum

[Objective] The aim of this study was to elucidate the quantitative traits of plants mutagenized by ion beam. [Method] The particular variation phenotypes, a- gronomic traits, and protein and wet gluten contents of progenies derived from the same ion beam induced mutant were investigated. [Result] Morphological polymor- phism existed in some individuals. Plant height, spike length and protein content were significantly influenced by ion beam, and effective tiller number and wet gluten content were moderately influenced. Multiple comparisons of all the indices within groups indicated genomic instability among these groups. Coefficient of variation im- plied the differences within group were very low. [Conclusion] Ion beam irradiation displayed characteristics of multi-directivity and non-directiveness. It aroused multiple variations in the same mutant. Instability among progeny indicates cells had different fate even in the same irradiated tissue. It may take several generations for mutants to stabilize particular phenotypes. The effects of ion beam irradiation may be the in- terrelated direct irradiation damage, indirect irradiation damage and late effect, such as bystander effect and adaptive response.