Effect of soil characteristics on N mineralization capacity in 112 native and agricultural soils from the northwest of Spain

N mineralization capacity and its main controlling factors were studied in a large variety (n=112) of native (forest, bush) and agricultural (pasture, cultivated) soils from several climatic zones in Spain. The available inorganic N content, net N mineralization, and net N mineralization rate were determined after 6 weeks of aerobic incubation. NH _inf4 ^sup+ –N largely predominated over NO _inf3 ^sup- -N (ratio near 10:1) except in some agricultural soils. Net N mineralization predominated (83% of soils) over net N immobilization, which was more frequent in agricultural soils (25%) than in native soils (9%). In forest soils, both net N mineralization and the net N mineralization rate were significantly higher than in the other soil groups. The net N mineralization rate of pasture and cultivated soils was similar to that of bush soils, but available inorganic N was lower. The net N mineralization rate decreased in the order: soils over acid rocks>soils over sediments>soils over basic rocks or limestone; moreover, the highest net N mineralization and available inorganic N were found in soils over acid rocks. The highest N mineralization was found in soils with low C and N contents, particularly in the native soils, in which N mineralization increased as the C:N ratio increased. N mineralization was higher in soils with a low pH and base saturation than in soils with high pH and base saturation values, which sometimes favoured N immobilization. Soils with an Al gel content of >1% showed lower net N mineralization rates than soils with Al gel contents of <1%, although net N mineralization and available inorganic N did not differ between these groups. The net N mineralization rate in silty soils was significantly lower than in sandy and clayey soils, although soil texture only explained a low proportion of the differences in N mineralization between soils.     

甲鱼出血性败血症的诊疗

简述了甲鱼出血性败血症的病症、病理变化、病原菌的分离和鉴定、动物回归试验的结果，以及采用敏感药物对患病甲鱼施治的经过和疗效。     

扇贝亲贝配合饲料的研究

“配合饲料”以植物蛋白质和碳水化合物为主，加以适量各种添加剂，经科学调配混合组成。蛋白质含量２５－２６％，脂肪８４－１２９％，碳水化合物４３－５６％，并含有扇贝亲贝性腺成熟必需的微量元素和其他促进性腺成长发育的重要成分。经饲喂试验表明：亲贝性腺指数提高２０－３０％，亲贝成活率９８％，比对照提高２６％，亲贝产出优质精、卵，受精卵的孵化率９３％，饲料成本降低５０％，是一种完全可以代替单胞藻喂养扇贝亲贝的优良配合饲料。     

油菜杂交种与亲本成熟期干重分配的差异

以6个甘蓝型常规油菜品种及其组配的30个杂交种为材料,设置N_0(不施氮)和N_1(150kg/hm~2)2个处理,研究杂交油菜与常规油菜各器官干重分配比例的差异。结果表明:(1)杂交种在N_0和N_1条件下籽粒产量分别比亲本高27.60%和18.12%,其主要原因是杂交种具有较多的角果数。(2)杂交种的茎秆和果壳重均显著高于亲本,但各器官干重所占的比例差异较小。     

蜘蛛人凤尾蕨采孢母株的选择和栽培技术研究

对蜘蛛人凤尾蕨的生物学习性、采孢母株的选择标准、植株对环境条件和肥水的要求以及病虫害的防治等方面进行了初步研究,为凤尾蕨属（Pteris）植物孢子穴盘育苗技术的研究奠定了基础。     

国审小麦品种偃展4110遗传基础分析及育成品种

对国审小麦品种偃展4110遗传基础进行分析,结果表明:偃展4110聚合了4个品种的优良基因,尤其是外源基因的导入和豫麦18的2次应用,使高产、早熟、抗病、抗倒、抗寒、抗干热风等优良基因在较高层次上得到了聚合重组,实现了丰产性与稳产性、早熟性与抗寒性的有机结合,从而促使偃展4110高产潜力加大,综合抗逆性增强,适应范围更广。最后对以该品种为亲本育成的新品种(系)进行了总结。     

高蛋白大豆杂交F_2代与亲本蛋白质含量的相关分析

以8个蛋白质含量不同的大豆品种或品系为亲本进行杂交,获得杂种F2代相关资料,从而分析杂种F2代蛋白质含量与亲本的相关关系。结果表明,双亲蛋白质含量差异大,F2代蛋白质含量变异程度也大;双亲蛋白质含量高,F2代蛋白质含量高;F2代蛋白质含量与母本及双亲中亲值呈极显著正相关,与产量呈负相关,与百粒重呈正相关;F2代蛋白质含量与亲本熟期差异呈负相关。     

安康引进桑品种饲养原蚕的研究

[目的]探讨安康新引进桑品种饲养原蚕制种的成绩。[方法]采用生物试验的方法,对几个新引进的桑品种进行饲养原蚕试验。[结果]引进桑品种对原蚕发育经过及生命率、茧质、卵质影响无明显差异,与对照品种相近,且秋蚕期各桑品种饲育原蚕的产卵平均良卵率均达到95.96%以上。[结论]桑品种强桑1号、陕桑305、金十、丰田5号、农桑14号、育71-1、湖桑32号均可用于秋期原蚕饲育。     

不同饲育回数对洞庭和碧波原蚕综合性状的影响

［目的］研究洞庭、碧波原蚕在贵州地理环境和气候条件下的性状表现。［方法］将洞庭、碧波原种催青收蚁后,以一日四回育为对照,设二回育和三回育2个试验区,各3次重复,小区蚁量1 g,于2009年春季开展全龄不同饲育回数的试验研究。［结果］全龄不同饲育回数对洞庭、碧波原蚕的发育经过没有明显影响,但对碧波原蚕的幼虫生命力和发育整齐度影响较大。其中,发育整齐度和眠起情况均以二回育区最不整齐,小蚕发生率为2.43%,分别是三回育和四回育的2.25、2.93倍;4～5龄期发病率和蔟中死蚕率均为0.50%,分别比三回育和四回育各高出0.32、0.17和0.32、0.17个百分点。洞庭品种4龄结茧率各处理间差异不显著,碧波品种4龄结茧率三回育和四回育与二回育之间均存在显著差异;洞庭、碧波品种对4龄健蛹率各处理间差异不显著;洞庭品种单蛾产卵量和单蛾良卵数四回育和三回育与二回育之间均存在显著以上差异,碧波品种各处理间产卵成绩差异不显著;洞庭、碧波品种单蛾不受精卵数和单蛾死卵数各处理间差异不显著。［结论］在贵州春季气候环境和桑叶基础条件下,洞庭、碧波原蚕采用全龄一日三回育完全可行,二回育不宜采用。     

定西市常用马铃薯亲本杂交效果的评价

应用杂交亲本12份,包括定薯1号、定薯2号、青薯2号、青薯6号、青薯7号、大西洋、新大坪、D1533、B47、陇薯3号、陇薯5号和陇薯6号,配制组合,研究如何利用这些亲本材料,结果表明:B47作母本时杂交坐果率最高,达到87.3%;父本中新大坪孕性最好,坐果率最高,达13.8%;另外B47、定薯1号、青薯7号和D1533都是既可作母本又可作父本的优良亲本材料。