农业空间诱变育种研究进展

报道了国内外空间诱变育种的情况，着重介绍了自1987年以来，我国科学工作者9次利用返回式卫星及5次高空气球搭载了60多种植物500多个品种的种子，经地面多年的选育，取得了一批可喜的成果。     

MCPB-ethyl疏花对富士苹果授粉受精及胚珠发育的影响

通过在花期用MCPB-ethyl处理,对富士苹果花粉的发芽、花粉管的伸长以及胚珠的发育等进行了形态方面的观察和探讨,以阐明MCPB-ethyl的疏花机制。结果表明,MCPB-ethyl对花粉的发芽及花粉管的伸长没有影响,整个受精过程与对照相同,没有发现异常。但受精后胚乳核只进行了数次分裂便停止生长,此后珠皮、珠心细胞迅速解体。根据以上结果,认为MCPB-ethyl的疏花效果不是通过影响花粉的发芽或花粉管的伸长阻碍受精所致,而是使胚和胚珠的发育停止,形成离层导致了落花。     

黄瓜单体异附加系的筛选与观察

 将甜瓜属异源三倍体与栽培黄瓜‘北京截头’杂交，经胚胎拯救获得了两个2n=15 (14C+1H)的单体异附加系，编号分别为02—17和02—39。02一l7植株叶形为戟形，02—39为深陷的掌状形，并且果刺均为白色，不同于异源三倍体的掌状心脏形和黑刺，果形比异源三倍体黄瓜长而更接近普通黄瓜。细胞学研究发现，单体异附加系在终变期和中期I染色体构型主要是由7个二价体和1个单价体构成，出现三价体的频率为4％ ～5％ ，中期Ⅱ不均等分裂形成不同的两极，一极染色体为8条，另一极为7条。RAPD分析证明它们分刖附加了野生种Cucum／s hystrix的染色体。     

真空渗入法转pinⅡ基因菜薹外源基因的遗传与表达

 本研究对利用真空渗入法获得的转bar基因及pinⅡ基因菜薹，进行了外源基因的遗传及表达情况分析。结果表明通过该方法获得的转基因植株，外源基因能够稳定遗传。bar基因在 代的分离大部分符合孟德尔遗传规律，但也有不符合的群体；pin II基因在 代中稳定表达，但各个株系之间的表达水平差异较大，因而各个株系的抗虫效果也具有显著差异，即使具有相同外源基因拷贝数的各个株系，其PIN I／蛋白表达量和抗虫效果也具有显著差异。     

黄瓜前中期染色体C - 分带及其制备方法研究

 以活体种子根为材料, 采用放线菌酮预处理, 直接获得了清晰的黄瓜前中期染色体C - 分带。黄瓜前中期染色体的长度介于3～8μm , 单套染色体组具有21 条稳定的C - 带, 包括12 条末端带、7 条着丝点带、1 条中间带和1 条随体带。还探讨了影响前中期C - 分带制备的关键因素, 提出了黄瓜前中期染色体C - 分带的实用制备方法。     

剪叶对茭白肉质茎膨大的影响

以 1个单季茭和 1个双季茭茭白品种为试材 ,在肉质茎开始膨大时进行不同程度的剪叶处理 ,结果表明 :各处理在开始膨大后最初几天内干、鲜质量差异不明显 ;剪去叶片对肉质茎膨大影响不大 ,但切除叶鞘后 ,肉质茎膨大初期以后的干、鲜质量显著下降 ;整株剪叶比单茎剪叶处理对肉质茎膨大的影响大 ,剪去叶片与切除叶鞘、叶片表现相似。由此认为 ,茭白肉质茎膨大所需养分主要依靠短缩茎和叶鞘在肉质茎膨大前的积累 ,肉质茎膨大过程中植株茎蘖间存在养分交流 ,品种间在膨大速率上有一定差异。     

优质白菜新品种‘暑绿’

 ‘暑绿’系白菜一代杂种，亲本为SW-13和SU-124(矮×苏)。该品种株型直立、束腰，叶片近圆形、翠绿色，叶柄半圆、绿白色。品质佳，株型美观，叶片与叶柄质量比值为0.67，单株质量0.40 kg。高抗炭疽病，抗TuMV、霜霉病和黑斑病。适宜在喜食青梗菜的地区作夏菜、秋菜和秋冬菜栽培。     

Relation between TNF-α,TNFR I expression and apoptosis in oral lichen planus

AIM: To examine the expression and distribution of tumor necrosis factor-α (TNF-α), tumor necrosis factor receptor I (TNFR I) and apoptosis in oral lichen planus, and evaluate their roles and relation in the oral lichen. METHODS: Immunohistochemical technique and TUNEL were employed to study the expression of TNF-α, TNFR I and apoptosis in 50 cases of oral lichen planus and 10 normal oral mucosa specimens. RESULTS: Compared with the normal control group, TNF-α expression was upregulated in mononuclear cells in lamina propria and decreased in keratinocytes in oral lichen planus lesion (P<0.05). On the contrary, TNFR I expression was increased in keratinocytes and decreased in lamina propria in oral lichen planus lesion (P<0.05). The increased apoptosis index in keratinocytes and the decreased apoptosis index in lamina propria were found in oral lichen planus (P<0.05). CONCLUSION: The accelerated apoptosis of keratinocytes and the inhibition of lymphocytes apoptosis may contribute to the formation and progression of oral lichen planus.     

隐性白肉鸡羽速自别雌雄系的选育(1)

本研究根据现代遗传学基因测交理论,共用32只表型慢羽公鸡与245只快羽母鸡组成测交试验.结果表明,所测的32只公鸡无一只为纯合慢羽基因型.但发现测交后代的快慢羽分布比例与孟德尔遗传上的分离定律完全吻合.同时通过混合精液输精,实施扩群繁育,其中选留慢羽种母雏1460只,表型慢羽种公雏150只,从而为建立隐性白鸡慢羽系奠定了基础.     

Polyphenols in Eucalyptus leaves improved the egg and meat qualities and protected against ethanol‐induced oxidative damage in laying hens

Polyphenols in Eucalyptus leaves (PE) were value resources due to various pharmacological activities, but data on the effect on laying hens are very scare. This study was conducted to determine the effect of PE on the laying performance, egg traits, meat quality, antioxidant status and liver tissues of laying hens. One hundred and twenty 256‐day‐old Yueqinhuang laying hens were randomly assigned to four treatment groups (different levels of PE at 0, 0.5, 0.8 and 1.2 g/kg diet) for 63 days with 15 replicates per group. Addition of 0.8 g/kg PE not only improved the egg trait by increasing the eggshell thickness and decreasing MDA production and cholesterol content in the egg yolk, but also significantly enhanced meat quality of hens, as suggested by the increase pH_45 min (p < .01) and a* value, and decrease drip loss rate (p < .01). Meanwhile, under acute ethanol‐induced oxidative damage condition, supplementation of 0.8 g/kg PE enhanced the serum antioxidant status by increasing enzymatic activities (GSH‐PX, T‐SOD, T‐AOC), inhibited oxidative damage and provided protective effect to liver tissue. In conclusion, addition of 0.8 g/kg PE not only improved the egg traits and meat quality without obvious adverse effects, but also increased the serum antioxidant status of the hens and protected their liver tissue from ethanol‐induced oxidative damage. This study indicated that PE could be utilized as an effective feed additive for laying hens to improve health performance and egg traits.