Mixed cropping with ice plant alleviates the damage and the growth of cowpea under consecutive NaCl treatment and after the recovery from high salinity

We investigated the alleviative effects of mixed cropping using ice plant, which is one of the salt-accumulating halophytes, on the damage and growth inhibition of cowpea, which is not tolerant to high salinity. Three cropping patterns (mono cropping of cowpea and ice plant and their combination) were tested. The plants were treated with 0, 100, 200 and 300 mM NaCl for 14 days (consecutive NaCl). The plants were also treated with NaCl for 3 days, followed by 2 weeks (short-term recovery) and 1 month (long-term recovery) recovery. Salinity levels for short-term recovery were similar to those of the consecutive experiment, while the concentration of long-term recovery was 250 mM. The alleviative effects of mixed cropping in the consecutive NaCl experiment were observed at 200 and 300 mM NaCl. Mixed cropping significantly reduced the Na content in the cowpea leaves at 200 and 300 mM NaCl compared with mono cropping. In addition, the Na content in the soil of mix-cropped cowpea at 200 and 300 mM NaCl was statistically lower than that of the mono cropping. Mixed cropping was effective to recover from high concentration of NaCl in the experiments of short- and long-term recovery. These results indicate that mixed cropping with a halophyte could be effective in mitigating the damage and growth inhibition of a glycophyte not only under salinity but also under recovery periods.     

2016年秋冠小白菜春秋两季多点比较试验

以华冠小白菜为对照品种,在大田生产条件下对秋冠小白菜进行新品种的多季多点比较试验,以期对新选育的秋冠小白菜的生物学性状、品质、产量等进行合理评价.结果表明:在多季多点试验中,新品种秋冠小白菜株高、株幅、叶长、叶宽、叶片数等均比对照表现好,株型紧凑,春、秋季平均667 m2产量分别比对照华冠提高18.5%、25.6%;抗病性及抗逆性均比对照强;维生素C、可溶性蛋白质、可溶性糖含量均较高,综合营养品质优良.     

施用生物有机肥对水晶蜜柚品质的影响

探讨生物有机肥与‘东试早’柚果实物理品质、化学品质及风味之间的影响,为德宏瑞丽地区‘东试早’柚适宜生物有机肥施用量提供参考。以11 年树龄‘东试早’柚为试材,测定‘东试早’柚果实物理、化学品质,并对果实进行感官风味品尝鉴定。结果表明,生物有机肥施用量30 kg/株,单果重、果肉重、纵径、横径最佳,此时还原糖、总糖、可溶性固形物和Vc含量最高,感官风味评价综合满意度分数最高。生物有机肥施用量增加到40 kg/株,单果重下降,可滴定酸含量显著升高,感官风味评价综合满意度分数有所下降。相关性分析显示,生物有机肥与还原糖、总糖、Vc和感官风味评价呈显著相关;感官风味评价的综合满意度与还原糖、总糖呈极显著正相关,与可滴定酸显著负相关。综合考虑‘东试早’柚的品质,生物有机肥用量以30 kg/株为宜。     

Marketing mix for the promotion of biological control among small-scale paddy farmers

Understanding farmers’ decision process on the adoption of biological control (BC) may help in promoting adoption. This study explored for the first time the impact of marketing mix elements (product, price, promotion, and place) on bolstering BC for the management of rice stem borer (Chilo suppressalis Walker) among rice farmers in Fuman County in northern Iran. Farmers using BC were familiar with this method primarily via village councils and rural municipality organizations (Dehyaris) and then via distributors of trichocards. Almost half of the farmers (48.3%) had weak to moderate level of contact with distributors of trichocards. All four elements (4Ps) of marketing mix (product, place, price, and promotion) were effective on the marketing of BC agents. Place (distribution) mix, followed by price mix, were the most important factors in marketing trichocards in farmers’ views. According to the sensitivity to 4Ps of marketing mix, most farmers were grouped as semi-sensitive (45.6%) and sensitive (39.4%). Overall, the availability of biological agent products in the market, the affordable price of the products, and the strong relationship of rural people with village councils and rural municipality organizations (Dehyaris) are crucial factors for BC promotion in paddy fields of Fuman.     

甜高粱特性及河北省研究利用现状

描述了甜高粱的生物学特性,对河北省甜高粱的育种和产业化状况进行了分析,并针对存在的问题,提出了合理化建议.这对于河北省发展甜高粱产业有一定的现实意义.     

基于细胞多层介电模型的脉冲电场生物学效应研究

为确定脉冲电场生物学效应的电场参数,从细胞多层介电模型出发,通过研究其等效电路模型在外加电场中生物响应的仿真分析得出植物细胞外膜具有低通滤波特性,内膜具有带通滤波特性。同时对细胞外膜跨膜电压进行时域分析表明频率小于2.83 Hz、电场强度大于69.7 kV/m、ms/μs级脉宽的极低频脉冲电场可以在植物细胞外膜产生可逆电穿孔。采用电场强度为100 kV/m、频率为1 Hz、脉宽为80 ms的极低频脉冲电场处理萌发绿豆种子,在萌发第4 d时,绿豆种子的芽长和根长分别比对照组增加了65.8%和80.2%。     

A yield-independent, 15N-isotope dilution method to estimate legume symbiotic dependence without a non-N2-fixing reference plant

The proportional contribution of atmospheric N₂ to the N nutrition of lupin (P _atm) was estimated in a field experiment following addition of NH₄Cl of KNO₃ to unconfined microplots (1.5 m²) at 2.5 g N m^-2 (10 atom% ¹⁵N). The integrated ¹⁵N enrichment, or mean pool abundance, of nitrate extracted from 0- to 15-cm samples taken under the lupin crop on eight occasion between 28 and 190 days after sowing was used as the reference criterion to estimate P _atm by the ¹⁵N-isotope dilution technique. Estimates of P _atm were similar to those obtained using canola as a non-fixing reference plant, but were higher than estimates obtained using a yield-dependent model. Use of mean pool abundance obviates the need for a non-fixing reference plant, and the frequent sampling and isotope-ratio analysis of the legume biomass required with the yield-dependent model is unnecessary. However, further work is needed to validate a sampling strategy commensurate with the growth of the legume roots.     

不同土壤中硅酸盐细菌生理生化特征及其解钾活性的研究

在以钾长石粉为唯一 K 源的硅酸盐细菌选择性培养基上,从我国部分省市土壤中筛选到 16 株硅酸盐细菌,以本实验室保藏 NBT 菌株为参照,对其生理生化特性、耐盐性、抗生素抗性、温度敏感性及释K 能力等生物学特性进行了测定。结果表明,17 株硅酸盐细菌菌体均为杆状,产生椭圆至圆形芽胞。其中 SB6、SB13 为短杆状,SB4、SB6、SB10、SB15 菌株是 G ,其余菌株是 G-。NH4 、NO3 为良好 N 源,且能在无 N -培养基上生长。菌株 SB13 和 NBT 解 K 能力较强,释放的 K 比接灭活菌对照分别增加 49.1 %和 45.3 %。菌株SB2、SB4、SB5、SB6 在 20 g/L NaCl 浓度的培养基上能生长,在温度为 10 ~ 40 范围内供试硅酸盐细菌能够良好生长。     

土壤养分有效性测定及其方法

在提出土壤养分有效性测定概念的基础上 ,本文对各种土壤养分有效性的测定方法进行了总结 ,讨论了这些方法的测定机理、测定效果及近几年的进展。这些方法包括用于磷钾等元素测定的树脂法、用于氮测定的生物培养法和化学提取法、磷测定的氧化铁试纸法和氢氧化铁透析管法和钾的四苯硼钠法     

嵌套子集:引入土壤多样性研究的讨论

嵌套子集指在任何特定集合中出现的物种趋向于在更大的集合中也出现,即局部丰富的物种一般分布比较广泛,而局部稀少的物种则分布较窄。本文对嵌套性研究中的有关问题做一评述,并以西班牙的一个研究为范例讨论可以看出,通过数据(土壤类型和土壤集合)试验得出的规律性和生态学上的观点竟非常相似。研究采用了土壤数据集和在计量生态学应用的方法,包括嵌套计算程序(Nested Calcu lator Program)。结果表明:嵌套性在生物群落、土被或土链结构中的性质有相似之处,即地学系统中普遍存在着嵌套性。此方法用于土壤多样性的分析,在有计划的保护生物及土壤资源方面具有现实意义。