大宗淡水鱼高温季节病害防与治

又到了一年一度大宗淡水鱼病害频发的高温季节,为此我们采访了相关病害专家,就大宗淡水鱼高温季节常见病害及病因、病害发生的新变化以及防治方法等进行了总结,供养殖户参考。     

自然养蜂的认证标准

我们都知道蜜蜂的健康受到受杀虫剂、单一农作物及病虫害的威胁,因此自然养蜂呈上升趋势,被认为是保证蜜蜂健康最有效的方法.目前有人已成为自然养蜂者,也有部分人将要加入这个行列.     

Effects of Lactic Acid Bacteria and Fructooligosaccharides on Growth Performance,Nutrient Digestibility and Serum Biochemical Indices of Arctic Foxes (Alopex lagopus) during Early Growth Period北大核心CSCD

This experiment was conducted to study the effects of dietary lactic acid bacteria (LAB) and fructooligosaccharides (FOS) on growth performance, nutrient digestibility and serum biochemical indices of Arctic foxes (Alopex lagopus) during early growth period. Sixty male post-litter Arctic foxes with the average body weight of (1.16±0.15) kg and at the age of (45±3) days were randomly assigned to 4 groups with 3 replicates per group and 5 foxes per replicate. The foxes were fed the following diets, respectively: basal diet (control group), basal diet+3×109 CFU / kg LAB (LAB group), basal diet+5 g / kg FOS (FOS group) and basal diet+3×109 CFU / kg LAB+5 g / kg FOS (LAB+FOS group). The experiment lasted for 30 days. The results showed as follows: 1) on the days 1 to 15, the diarrhea rate of foxes in the LAB group and LAB+FOS group was significantly lower than that in the control group and FOS group (P<0.05). On the days 16 to 30, the average daily gain of foxes in the LAB+FOS group was significantly higher than that in the control group and FOS group (P<0.05), but had no significant difference with LAB group (P>0.05); the diarrhea rate of foxes in the LAB+FOS group was significantly lower than that in the control group and FOS group (P<0.05), but had no significant difference with LAB group (P>0.05); compared with the FOS group, the feed to gain ratio of foxes in the LAB+FOS group was significantly decreased (P<0.05). 2) The dry matter digestibility of foxes in the LAB + FOS group was significantly higher than that in the control group and FOS group (P < 0.05), but had no significant difference with LAB group (P>0.05). There were no significant differences in nitrogen intake, fecal nitrogen, urine nitrogen, nitrogen deposition, net protein utilization and protein biological value among all groups (P>0.05). 3) Serum total protein (TP) content of foxes in the LAB+FOS group was significantly higher than that in the FOS group (P<0.05), but had no significant difference with control group and LAB group (P>0.05). Serum albumin (ALB) content of foxes in the LAB group was significantly higher than that in the control group and FOS group (P<0.05), but had no significant difference with LAB+ FOS group (P>0.05). Serum urea nitrogen (UN) content of foxes in the LAB+FOS group was significantly decreased compared with the control group (P < 0. 05). In conclusion, the combined supplementation of 3 × 109 CFU / kg LAB and 5 g / kg FOS in the diet is beneficial to reduce diarrhea rate, improve dry matter digestibility, improve body immune level, and promote the growth of Arctic foxes during early growth period. © 2023 Chinese Journal of Urology. All rights reserved.     

盐胁迫对裸果木幼苗光合特性的影响

本研究以一年生裸果木幼苗为材料，采用盆栽育苗方式，设计7个不同浓度NaCl溶液（CK、0.2%、0.4%、0.6%、0.8%、1.0% 和1.2%）模拟盐分胁迫，测定分析了其叶片气体交换参数、光响应曲线及叶绿素荧光参数的变化规律。结果表明：随着盐浓度的增加，叶片净光合速率（P_n）、气孔导度（G_s）和蒸腾速率（T_r）均呈下降趋势，NaCl浓度≥0.4%时，各处理P_n、G_s和T_r均显著低于CK；气孔限制值（L_s）和瞬时水分利用效率（WUE）随盐浓度增加呈先升后降趋势，胞间CO₂浓度（C_i）呈相反趋势，NaCl浓度为0.4%时，L_s达到最大值，而C_i达到最小值，说明P_n下降以气孔限制因素为主，而当NaCl浓度≥0.6%时，以非气孔限制为主要因素。随着盐胁迫程度的增大，最大净光合速率（P_nmax）、暗呼吸速率（R_d）、光饱和点（L_SP）、表观量子效率（A_QY）逐渐降低，光补偿点（L_CP）逐渐增加，表明盐分抑制了幼苗对光的吸收、利用和转换能力。叶片PSII潜在活性（F_v/F₀）、原初光能转化效率（F_v/F_m）、实际光化学效率（Φ_PSII）、电子传递速率（ETR）和光化学猝灭系数（q_p）随着盐浓度的增加呈下降趋势；非光化学猝灭系数（NPQ）在≤0.4%NaCl处理下较CK显著增加，盐浓度≥0.8%时，NPQ显著下降。基质的NaCl浓度在0.2%和0.4%时，裸果木叶片P_n、F_v/F₀、F_v/F_m下降不显著，WUE有所提高，PSII系统可以通过耗散过剩的光能保护光合机构，表现出一定的耐盐性；但盐浓度超过0.6%时，光合生态幅变窄，光合机构受到明显破坏，显著抑制了光合作用能力。     

小浆果开启致富大门——新疆阿勒泰农民发展浆果产业记

<正>2011年,正值新疆阿勒泰地区以沙棘为主的特色小浆果产业起步之时,新一轮的援疆开始了,黑龙江省对口支援阿勒泰地区,黑龙江省林业厅多次派人来阿勒泰地区调研,制定了一系列助推小浆果产业发展的措施。黑龙江省林业厅派出专家,把在黑龙江省已成熟的沙棘种植技术和产业发展经验向阿勒泰地区交流传授,最终确定了以产业援助的形式,大力支援阿勒泰地区发     

智慧农业 让山西农民挣更多的钱

<正>曾经全靠人工的农活儿,在机械、新技术的助力下,逐渐变得轻松。如今,智慧农业已不再是梦想。机械做记录农产品插上翅膀西红柿不是长在土里,而是在水里培养;稻田里,植保无人机在空中盘旋喷药;温室大棚的光线能自动调整,果蔬需要快速生长时光线直射,需要慢生长时则可斜射;扫二维码就能查到农产品的种子来源、施肥、用药情况……以上这一切不是未来,是山西已经实现了的智     

单胃动物脂肪营养研究进展

Fat is an essential element for animal.The paper reviewed recent research progress on fat nutrition in monogastric animal at home and abroad, combining with the fat digestion and absorbing form in animal body, and summarized biological function and application of fat in production, so as to provide theoretical basis for better utilization of fat in animal production and exploration its mechanism of action.     

反季节苦瓜水肥一体化栽培关键技术

水肥一体化技术是将灌溉与施肥融为一体的农业新技术。本文从苦瓜的特性、播种期选择、播种、育苗、定植、植株管理、肥水管理等出发,介绍了水肥一体化技术在反季节苦瓜栽培上的应用,及其显著的社会、经济、生态效益。