母猪营养利用模型研究:优化营养供给的途径(续完)

近年来,母猪的繁殖性能得到了极大的改善。现在,许多养猪场都使用高产母猪,这些母猪的平均窝产仔数超过13头,窝断奶仔猪数超过11.5头。这些变化对母猪在怀孕和哺乳期间的营养需要量产生了重大的影响。同时,过去20年,母猪能量、氨基酸和矿物质利用方面取得的成果使确定母猪的营养需要(析因法)和预测它们对营养物质供给(建模)的反应成为可能。本文旨在介绍如何将现有的母猪营养方面的知识集合于一个综合模型中并转化为软件工具,供给终端用户,主要是给养猪企业的广大营养师和动物营养专业的学生使用。文章列举的各个案例用来说明使用此类模型如何能够优化母猪生产力,同时优先考虑一些新的因素,如通过根据需要更精准地调整营养供给以达到减小养猪生产对环境的影响。     

蕈菌的栽培及其对环境的影响(四)

正6经济和社会效益据估计~([67]),超过70%的农业和林业作物被认为是无用的材料或是不可食用的废物/副产品而被丢弃。例如:剑麻中仅有2%的纤维被提取利用,其余98%作为废物丢弃;蔗糖仅占植物生物量的17%,其余83%则以甘蔗渣的形式弃置;在棕榈椰子种植园产生的总生物量中,提取的油只占5%,其余95%是废物;世界各地的树木遭砍伐,而其目的主要是为了获得木材中占比甚微(硬木中纤维素占比为30%,软木为20%)     

Autochthonous halotolerant plant growth-promoting rhizobacteria promote bacoside A yield of Bacopa monnieri (L.) Nash and phytoextraction of salt-affected soil

Phytoremediation is a promising approach for reclamation of salt-affected soil. Phytoextraction is the most commonly used process, which exploits plants to absorb, immobilize, and accumulate salt in their shoots. In this study, halotolerant plant growth-promoting rhizobacteria (PGPR) were isolated from the rhizosphere of wild grasses growing naturally in salt-affected areas of Lucknow, Uttar Pradesh (India) and were tested for their efficacies of salt-tolerance and plant growth-promoting (PGP) abilities. Based on 16S rRNA sequences, the most efficient halotolerant isolates possessing PGP traits were identified as Pseudomonas plecoglossicida (KM233646), Acinetobacter calcoaceticus (KM233647), Bacillus flexus (KM233648), and Bacillus safensis (KM233652). Application of these isolates as bio-inoculants significantly (P < 0.05) increased the growth and bacoside A yield of a medicinal plant, Bacopa monnieri (L.) Nash, grown on natural salt-affected soil. The phytoremediation of salt-affected soil was evident by the substantial increase in shoot Na⁺:K⁺ ratio of bio-inoculant-treated plants. When compared to un-inoculated control plants, the soil physico-chemical properties of bio-inoculant-treated plants were improved. The shoot and root biomass (fresh and dry weights), soil enzymes, and soil nutrient parameters showed significant positive correlations with the shoot Na⁺:K⁺ ratio. Consequently, the halotolerant PGPR screened in this study could be useful for the reclamation of saline soils concomitant with improved plant growth and bacoside A yield.     

Bacterial communities associated with natural and commercially grown rooibos (Aspalathus linearis)

Aspalathus linearis is a commercially important plant species endemic to the Cape Floristic Region of South Africa and is used to produce a herbal tea known as rooibos tea. Symbiotic interactions between A. linearis and soil bacteria play an important role in the survival of Aspalathus plants in the highly nutrient-poor, acidic fynbos soil. The aim of this study was to characterize and compare rhizosphere and bulk soil bacterial communities associated with natural and commercially grown A. linearis, as well as the effect of seasonal changes on these communities. Bacterial communities were characterized using high throughput amplicon sequencing, and their correlations with soil chemical properties were investigated. The N-fixing bacterial community was characterized using terminal restriction fragment length polymorphism and real time quantitative polymerase chain reaction. Actinobacteria, Proteobacteria, and Acidobacteria were the most dominant bacterial phyla detected in this study. Highly similar bacterial communities were associated with natural and commercially grown plants. Significant differences in the bacterial community were observed between rhizosphere and bulk soils collected in the dry season, while no significant differences were detected in the wet season. This study provides insights into bacterial community structure and potential factors shaping bacterial community structure with commercially important A. linearis.     

吐鲁番市葡萄绿枝扦插育苗技术探究

文章以吐鲁番市葡萄绿枝扦插育苗技术为研究对象,首先分析探讨了扦插前需要进行的一些准备工作,比如准备还苗床,做好普通插条采集,加强葡萄插条管理,随后对葡萄具体扦插育苗进行了分析,最后立足于普通扦插育苗后续管理,分析了葡萄剪枝、病虫害防治等,以供参考。#$NL关键词：吐鲁番；葡萄育苗；绿枝扦插育苗技术     

浅谈全方位深松技术改善低产田的作用及技术要求

<正>深松是指疏松土层而不是翻转土层的土壤耕作技术,深松既可以作为秋收后主要耕作措施,也可用于春播前的耕地、休闲地的松土、操场更新等。深松有全面深松和局部深松两种。全面深松是用深松机在工作幅宽上全面松土,这种方法适用于配合农田基本建设,改造耕层浅的粘质土。局部深松是用杆齿、凿形铲或铧进行间隔的局部松土。深松具体形式有:全面深松、间隔深松、浅翻深松、灭茬深松、中耕深松、垄作深松、垄沟深松等。深松的深度视耕作后的厚度而定。一般中耕深松深度     

储粮生态系统的跨学科和多学科研究——加拿大曼尼托巴大学在粮食储藏研究上的最新进展

加拿大曼尼托巴大学的跨学科储粮研究团队对储粮生态系统的各个方面进行了系统的研究。该团队的最新研究活动包括:储粮生态系统建模,粮堆热点的发生和安全储存条件,粮堆气流流动,害虫在粮堆中的迁移、分布与对其取样、诱捕的关系,以及计算机图像处理技术。这些研究增进了我们对储粮生态系统的认识与理解,为粮食储运的安全性及高效率技术创新奠定了基础。