Study On Application Of Four Nude PTGMS Lines In Rice

In this study,the morphological characteristics,reproductive characteristics and out-crossing characteristics of four new nude photo-thermo sensitive genetic male sterile(PTGMS)lines of rice(7CS102,X8S010,8CS963,X6S1791)by using Y58 S as one of their parents and control Y58 S were studied.Meanwhile,thirty hybrid combinations were made up by using incomplete diallel crossing with two non-photoleaf restorers(R028,H070)and four photoleaf-restorers(X9H001,X9H002,X9H003,X9H005)and five photo-thermo sensitive genetic male sterile lines.By analyzing the rice quality characters of 30 combinations when they were planted as middle-season and late-season rice,the combining ability of rice quality related characters was analyzed.At the same time,the difference of rice quality between the two seasons was discussed,in order to provide the theoreti-cal basis and reference for the breeding of the Nude PTGMS Line,and its application in thebreeding of high quality rice.The main results are as follows:(1)The leaves and glumes of the four nude PTGMS lines were smooth and hairless,the upper three leaves were long,straight and wide,the leaf sheath was longer than Y58 S,the ear length was longer than Y58 S except X6S1791.Nude PTGMS lines 8CS963,X8S010 and 7CS102 had the characteristics of strong tillering ability,large panicle and many spikelets,and had good yield.The rice quality of 8CS963 and X8S010 reached the third grade edible indica rice variety standard of agricultural industry standard,the content of amylose of X6S1791 was higher,the content of amylose of 7CS102 was lower.(2)The starting temperature of fertility transformation of four nude PTGMS lines was between22.5 ℃ and 23.5 ℃.The results showed that the flowering duration of the four lines was short,the flowering rate of X8S010,8CS963 and 7CS102 was higher than that of Y58 S before noon,the stigma lateral exposure rate,bilateral exposure rate and total exposure rate of 8CS963 were not significantly different from those of Y58 S,while the stigma lateral exposure rate rate and total exposure rate of the other three lines were not significantly different from those of Y58 S,but the bilateral exposure rate and total exposure rate of stigma were lower than those of Y58 S.(3)Combining ability analysis of the main agronomic characters of the tested combinations showed that plant height,effective panicles number and total grains per panicle were affected by gene additive effect,seed setting rate and yield per plant were affected by gene non-additive effect,panicle length,thousand grain weight,primary branch number per panicle,the length of sowing date to heading date were affected by gene additive and non-additive effect,and were greatly affected by restorer lines except thousand grain weight.Nude PTGMS lines X6S1791,8CS963 and 7CS102 had good general combining ability of agronomic characters.The results showed that the three nude PTGMS lines were easy to breed hybrid combinations with good agronomic characters.(4)The analysis of rice quality characters of 16 bare hybrid rice combinations showed that the quality of bare hybrid rice combination was better than that of non bare hybrid rice.Alkali elimination value is the main quality character that affects the quality grade of bare hybrid rice.The improvement of alkali elimination value should be paid attention to the breeding of bare hybrid rice.(5)Combining ability analysis of the rice quality characters of the tested combinations were planted as middle-season and late-season rice showed that the rice milling quality was mainly affected by the additive effect of parents,and the effect of male parent was greater.The length,the width and the length/width of grain were controlled by both additive and non-additive effects,but mainly by the additive effect of parents,and the effect of sterile lines was greater.The chalkiness character was controlled by both additive effect and non-additive effect,but mainly by the additive effect of parents,and the effect of male parent was greater.The content of amylose was mainly affected by the additive effect of the sterile lines,and the alkali spreading value and gel consistency were mainly affected by the non additive effect.(6)The results showed that X6S1791 was easy to breed hybrid combinations with better milling quality,7CS102 was easy to breed hybrid combinations with better appearance quality,8CS963 was easy to breed late-season hybrid combinations with better appearance quality,X8S010 and 8CS963 were easy to breed middle-season hybrid combinations with better cooking quality.(7)The stability analysis of the rice quality characters of the tested combinations were planted as middle-season and late-season rice showed that high temperature is not conducive to the improvement of rice milling quality,and has a relatively large impact on the head rice rate.At the same time,high temperature increased chalkiness of rice grain and reduced amylose content and gel consistency length and alkali spreading value,but had little effect on gel consistency length.The milling quality of the hybrid combination of four nude PTGMS lines and Y58 S was stable,the milling quality of the hybrid combination of male parent H070 was poor,the appearance quality of the hybrid combination of male parent R028 was stable,the hybrid combination of sterile line X6S1791 was stable on the content of amylose,and the stability of gel consistency of the hybrid combination of four nude PTGMS lines and Y58 S was good.