同源四倍体水稻与狼尾草杂交结实的胚胎学证据

在以6份同源四倍体水稻为杂交母本与狼尾草进行属间杂交中发现,其结实率达到0.84%～2.06%,而在以二倍体水稻为母本的属间杂交中却没有获得结实种子.利用激光扫描共聚焦显微技术对属间杂交结籽的特殊生殖现象进行了观察研究,试图寻找其杂交结实的胚胎学证据.结果表明,狼尾草的花粉粒不能在二倍体水稻的柱头上萌发,说明二倍体水稻与狼尾草的生殖隔离很严格,两者很难杂交.然而,狼尾草的花粉粒在同源四倍体水稻的柱头上能萌发,花粉管能在花柱中伸长并能将雄配子送入胚囊内与雌配子融合成受精卵.同源四倍体水稻与狼尾草的受精作用比较特殊,包括精细胞与卵细胞的单受精作用、精细胞与次生极核的单受精作用和正常的双受精作用,总受精率和总成胚率分别为6.36%～11.68%和4.11%～9.44%.试验结果为解释同源四倍体水稻与狼尾草杂交结籽的特殊生殖现象提供了有力的胚胎学证据.     

播量对水稻生长发育及干物质积累的影响

用盆栽方法进行播量对寒地水稻生长发育及干物质积累影响试验,结果表明:稀播的秧苗发根力强、分蘖多、茎基宽、充实度高。播量200g/m2的产量最高。     

杂交早稻吸氮特性与产量形成的初步研究

研究了在不同施氮水平下,杂交早稻吸氮特性及其与产量形成的关系。结果表明;杂交早稻威优49亩产500千克左右,植株每亩总吸氮量平均为9.78千克,其中土壤供氮量占52.45%。杂交早稻一生中前期吸氮量占50.72%,中期占31.08%,后期占18.30%,以中期施氮对叶片含氮率影响最大。在高氮水平下,中期施氮导致茎鞘醣含量急剧下降。抽穗前植株吸氮量与每亩发育颖花数呈极显著正相关,但结实率受每朵颖花占有抽穗前醣量的影响。最适 LAI 为6.5～7.5。     

水稻香亭病(Balansia oryzae-sativae Hashioka)--一种影响杂交水稻种子出口的病害

水稻香亭病（Balansia oryzae-sativae Hashioka）,又被称为水稻＂一柱香＂病（Ephelis oryzae Sydow）,是当前影响杂交水稻种子出口的一种真菌病害.从该病原菌的命名、分布、寄主、生物学特性、危害症状、经济损失、检测方法和防治等方面进行了概述.     

矸酆恐?,垩白率与糙米率、蛋白

Χ灾绷吹矸酆康挠跋焓钦?,直接影响比间接影响大。Study on the correlation between rice quality and agronomic traits of quality riceNIE Cheng rong, WEN Yu hui, WANG Yun bo, CHEN Ming zhong,LI Mei, LIU Dao quan(Agronomy Department, Foshan University , Nanhai 528231,China)The correlative analy     

Changes in Endopeptidase Activity during Photosynthetic Declination in Rice Leaf

Two japonica rice varieties, Wuyujing 3 and 97-7, were used to study the changes in contents of soluble protein, free amino acids and endopeptidase activity during photosynthetic declination. The content of soluble protein in flag leaf of cv.Wuyujing 3 was higher than that of cv. 97-7, but decreased rapidly in Wuyujing 3. Free amino acids in flag leaf and the thirteenth leaf of Wuyujing 3 started to increase 10 days before the turning point of photosynthetic declination (TPPD), while it occurred just 1-2 days before TPPD in the flag leaf and the thirteenth leaf of 97-7. During reversible phase of photosynthetic declination,endopeptidase activity remained at a low level and increased slightly only in the later part of this phase. Then it rose up rapidly at irreversible decline phase and reached a very high level. For Wuyujing 3, the change in endopeptidase activity in the thirteenth leaf was parallel to that in flag leaf. However, for 97-7, the rapid increase of endopeptidase activity in the thirteenth leaf started later than that of flag leaf. The results implied that the rate of protein breakdown and conversion to transportable nitrogen in leaves of 97-7 was slower than that in leaves of Wuyujing 3 during photosynthetic declination and it led to relatively lower seed setting rate and fully filling grains rate in 97-7. This may be one of the important reasons why 97-7 could not bring the high yield potentiality into play and the findings may be taken into consideration while breeding for high potential varieties in future.     

Influence of Low Light Irradiance on Grain Filling in Rice (Oryza saliva L.) cultivars

Time course of grain filling pattern in two rice (Oryza sativa L.) cultivars, grown under normal and low light intensities, was studied. The number of spikelets, partially filled grains and high density grains were monitored at a 5 day interval during grain filling period from uniform panicles tagged at anthesis. The low light tolerant cultivar Swarnaprabha had more high density grains and less partially filled grains throughout the grain filling period and at harvest compared to cultivar Ratna under both normal and low light intensities. Further, the opening of spikelets in two flushes in Swarnaprabha seemed to result in a more efficient resource allocation and hence better yield as compared to Ratna, in which the opening of spikelets was in a single flush on day 10.     

一种适合稻区紫云英生产实际的紫云英加工调制方式

将紫云英鲜草分离为草汁、细渣、纤维状渣；以粉状能量精料为载体吸收汁液；3种制品都以晾晒的方式进行干燥。晾晒时，3种制品综合占场面积较原草减少近90％；3种制品均可在一个晴日内风干，比原草干燥速度提高一倍余；细渣品质与国标一级苜蓿草粉相当；“二次拌汁料”、“三次拌汁料”之粗蛋白、粗纤维含量符合生长肥育猪饲养标准；加工方式切合稻区紫云英生产实际及产区综合条件，有推广价值，且易推广。     

水稻籼粳核质核杂种研究初探

籼质粳核核质杂种配普通籼稻,粳质籼核核质杂种配普通粳稻,以及这两种核质杂种互交F1,称之为核质核杂种.研究表明,核质核杂种既保持了或基本保持了籼粳稻亚种间的杂种优势水平,又克服了籼粳稻亚种间不亲和的问题、植株超高问题和不能正常抽穗等问题.探索了一条亚种间杂种优势利用的新途径.     

制糖废水处理方法研究进展

制糖废水是一种高浓度的有机废水 ,如何高效处理是环境工程研究的一个重点。本文就其国外最新的研究成果进行了总结