利用子房培养选育Brassica juncea和Diplotaxis virgata的属间杂交种及后代的细胞学和杂交能力

对属间F1杂种、F2和回交子代(BC1)进行了细胞学研究。所用材料为Brassica juncea(2n=36)和Diplotaxis virgata(2n=18).利用子房培养在2个种间产生了3个属间F1杂交种，它们具有36条染色体。这些染色体可能由B．jzncea的一个染色体组和D．virgata的2个染色体组组成。叶子的形态类似B．juncea。而花瓣的颜色为黄色，并且像D．

硬粒小麦与玉米杂交力的变异

为了检测硬粒小麦与玉米杂交力的变异情况，将两套硬粒小麦材料和硬粒小麦品种Ｌａｎｇ－ｄｏｎ的一套Ｄ组染色体代换系与玉米杂交，然后将分蘖分开，进行液体培养，并进行２，４－Ｄ或硝酸银处理（即给分蘖培养液中加入２，４－Ｄ或硝酸银）。结果表明，硝酸银使２５个硬粒小麦育种系×玉米的胚形成百分率由１．４％提高到了２．８％。在３２个硬粒小麦材料（高代品系和品种）与玉米的杂交中，加入硝酸银后的胚形成频率为０～１５．８％；其中有７个基因型的胚形成频率高于６．０％，这与它们的系谱有关。一套染色体代换系与玉米杂交后，其胚形成频率为０．４％～５８．１％，其中具有１Ｄ、３Ｄ、４Ｄ和７Ｄ染色体代换系的胚形成频率较高。这些结果表明：①给２，４－Ｄ处理液中加入硝酸银可以提高平均胚形成频率，但总体看来对硬粒小麦种子和胚的发育无明显效应；②将有些Ｄ组染色体转入硬粒小麦遗传背景后能够提高其杂交力。

荞麦物种Big—Achene组群的细胞学同功酶和种间杂交研究

荞麦有很高的营养价值，其种子蛋白质的氨基酸组成接近标准蛋白质品质，并且蛋白质优于禾谷作物的。本试验根据种间杂交COT(即谷氨酸草酰乙酸转氨酶)同功酶显带特征和细胞学研究了8个物种的11个种质品系；这8个物种属于Fagopyrum Mocnch属的big—achene组群。在这8个物种间正常传粉后存在较高的杂交能力(8-37％)，

Positive effect of porphyrans on the lifespan and vitality of Drosophila melanogaster

The effects of degraded porphyran (P1) and natural porphyran (P) on the lifespan and vitality of Drosophila melanogaster are studied. The porphyrans, added daily to the food medium at 0.2% and 1% concentrations, can significantly increase the lifespan in average of 55.79 and 58.23 d in 0.2% P1 diet females and 1% P1 diet males, extending by 12.29% and 8.60% over the corresponding controls, respectively. The effects of porphyrans on D. melanogaster in heat-stress condition were also examined, and found a remarkable increase in survival time. The results which are consistently associated with the use of porphyrans are related to their free radical scavenger action. Considerable increase in vitality demonstrated that vitalities of middle-aged fly (assessed by measuring their mating capacity) was observed after porphyrans addition. Therefore, porphyrans are effective in reducing the rate of aging, and P1 in low molecular weight is better than natural P.