Aim: The objective of the present study is to know the effect of feeding processed sweet sorghum (Sorghum bicolour (L) moench) crushed residue (SSCR) based complete ration on growth, feeding behavior and cost of gain in Murrah buffalo calves in order to compare the feeding value of SSCR with sorghum straw (SS) and also find out the efficient way of utilization of SSCR in the diets of growing buffalo calves. Materials and Methods: Experimental complete rations were formulated with SSCR and concentrate in 50:50 ratio and processed in to SSCR chopped and concentrate (SSCRC), mash (SSCRM) and expander extruder pellets (SSCRP). The control ration was SS based complete feed processed in to mash (SSM). 24 Murrah buffalo calves (Average 137 kg body weight and aged 1 year 2 months) were randomly distributed into 4 experimental groups of 6 animals each in a completely randomized design and the experimental rations were offered to 4 groups randomly for a period of 150 days. A 7 day digestion trial was conducted at the end of 150 day growth trial to find out the nutrient digestibility of experimental rations. Eating and ruminating activities were noted every 5 minutes, and each activity was assumed to persist for the entire 5 minutes. Sorting behavior in the calves was observed physically at the time of feeding. The cost of the rations was calculated on the basis of processing cost and the prevailing market prices of the feed ingredients. Results: The DM intake (g/d), digestibilities of DM, organic matter, crude protein and nitrogen free extract and nitrogen (N) balance were higher (P<0.05) in buffalo calves fed SSCRP ration but, comparable among SSCRC, SSCRM and SSM rations. Higher (P<0.01) average daily gain (g), lower feed conversion ratio (FCR) was observed in calves fed SSCRP ration, while comparable among SSCRC, SSCRM and SSM rations. Eating, rumination and total chewing time (minutes/d,minutes/kg DMI and minutes/kg NDFI) and number of chews for eating, rumination and total chewing (per d, per kg DMI and per kg NDFI) were higher (P<0.01) in calves fed SSCRC ration and lower (P<0.01) in SSCRP ration and comparable among SSCRM and SSM rations. Sorting and selection of ration against large fibrous particles in favour of concentrate portion of the ration was observed in SSCRC ration and was not observed in SSCRP, SSCRM and SSM rations. lower (P<0.05) cost (INR) per kg gain was observed in buffalo calves fed SSCRP ration than those fed SSCRC, SSCRM and SSM rations. Conclusion: The present study indicated that SSCR may be used as roughage source in place of SS in c

采用3因素裂区设计,研究4个甜秆饲草高粱品种在不同种植密度和刈割次数下的植株性状及产量的差异。结果表明：在饲草高粱生育进程中,无论刈割1次还是2次,14万株·hm^-2高密度种植的鲜草产量总是高于10万株·hm^-2的低密度处理;增加刈割次数可有效地增加甜高粱的总产草量。采用植株高大茎秆粗壮的623A×126-524、高密度14万株·hm^-2种植和一生刈割2次是本试验条件下产草量高的最佳组合,该组合鲜草产量可以达到84 039.67kg·hm^-2,且在刈割1次的情况下该杂交组合的籽粒产量也达到最大。另2个甜秆饲草杂交高粱鲜草产量都极显著高于甜高粱1号。以上结论可以为选用合适的甜高粱品种进行合理密植、提高产草量从而促进饲草利用提供强有力的技术支撑。

为筛选适合甜高粱青贮的青贮菌剂,以饲用型甜高粱和醇用型甜高粱渣为研究材料,添加不同的青贮菌剂对其青贮,青贮90 d后通过测定青贮料的p H值、中性洗涤纤维、粗蛋白、挥发性脂肪酸、干物质等成分,对青贮过程中不同的青贮菌剂对青贮品质的影响进行评价分析。结果表明:在添加不同的青贮菌剂青贮后,与对照相比,青贮料的p H值、中性洗涤纤维含量都显著(P0.05)降低,乳酸含量显著(P0.05)提高。自制的甜高粱青贮菌剂在青贮饲用型甜高粱后,FHI菌剂处理组总糖含量最高,比对照提高了7.88%,比美国、台湾菌剂分别提高了4.89%、1.82%;而在青贮醇用型甜高粱渣时,FHIIL菌剂处理组粗蛋白含量最高,较对照提高了18.61%,比美国、台湾菌剂分别提高了12.95%、3.4%。因此,FHI甜高粱青贮菌剂适合饲用型甜高粱的青贮,而FHIIL、FHIII青贮菌剂则更适合于醇用型甜高粱的青贮。

牧草是畜牧业发展的重要物质基础,加快发展牧草产业,是减轻饲料粮对粮食安全压力的有效途径。鉴于我国北方地区牧草生产压力大,基于区域自然资源禀赋、育种与推广成效、发展规模与模式等视角,探讨了南方地区牧草产业发展的可行性及其前景与效益。研究表明,南方地区牧草产业发展有着良好的自然资源优势,优质品种育种与推广成效显著,牧草种植初具规模,探索形成了适宜区域特点的种植模式;草商品市场需求强劲,南方地区发展牧草产业有着巨大的潜力和社会经济效应;但也面临着土地不平、技术不高、政策不全、体系不完善等问题,新时期亟需制定牧草种植补贴政策,完善生产经营体系,加大技术研发投入,实施优质草种繁育基地建设工程、优质饲草基地建设工程、草地畜牧业示范基地建设工程等一揽子重大工程项目,支撑南方牧草产业的发展。

甜高粱作为青贮饲料具有诸多优势，本文对甜高粱用作青贮饲料的研究与利用现状进行了综述，包括以下几个方面：（1）甜高粱用作青贮的品种优势；（2）甜高粱青贮的关键技术；（3）甜高粱青贮饲料饲喂效果。并对甜高粱青贮饲料发展前景及今后的工作重点作一展望。

比较38%莠去津悬乳剂、20%烟嘧.莠去津可分散油悬浮剂、20%氯氟吡氧乙酸浮油、41%草甘膦异丙胺盐水剂4种除草剂对高粱田苗后杂草的田间防效及药害程度。结果显示:20%氧氟吡氧乙酸乳油对高粱田杂草有较好的防除效果,防效可达85.8%,同时对高粱没有明显药害。

为了明确莠去津土壤残留对后茬蔬菜的影响，在室内采用毒土添加法研究了莠去津不同土壤残留量对黄瓜、豇豆、辣椒和菜薹光合作用和幼苗生长的影响。结果表明：莠去津土壤残留量为0．21、1．84、0．24、0．11mg·kg-1时，导致黄瓜、豇豆、辣椒和菜薹叶片PsⅡ最大光化学效率（Fv／Fm）下降10％；4种蔬菜分别在接近此有效成分剂量时（黄瓜0．2mg·kg-1、豇豆2mg·kg-1、辣椒0．2mg·kg-1、菜薹0．1mg·kg-1），电子传递速率（ETRⅡ）显著下降，且单株鲜质量抑制率达到50％；4种蔬菜对莠去津土壤残留的敏感性顺序为：菜薹〉黄瓜〉辣椒〉豇豆；Fv／Fm可作为早期预知轮作蔬菜是否受到莠去津残留潜在药害的指标，Fv/Fm的ID10为轮作蔬菜是否受药害的临界值。

为探索防治高粱田杂草的适宜除草剂类型及其对高粱的安全性,采用田间小区试验,分别进行了4种播后苗前封闭除草剂和9种苗后除草剂对高粱田杂草的防除效果、高粱生长的安全性评价以及对高粱产量的影响研究。结果表明:播后苗前封闭处理的药剂为38%莠去津和二甲戊灵混合组合,使用剂量为(1995 g+1950 m L)/hm2,苗后茎叶处理的有效药剂有50%二氯喹啉酸450 g/hm2+50%氯氟吡氧乙酸异辛酯900 m L/hm2、10%乙羧氟草醚450 m L/hm2+50%乙草胺1350 m L/hm2、50%氯氟吡氧乙酸异辛酯900 m L/hm2+50%乙草胺1350m L/hm2,或单施10%乙羧氟草醚450 m L/hm2。以上5种药剂对高粱田杂草有很好的防除效果且对高粱生长安全,高粱产量也有显著提高。

[目的]探讨3种除草剂在高粱不同生长时期施用的除草效果及对高粱生长和产量的影响。[方法]使用农达、38%琇去津、史它隆3种除草剂对泸糯8号和泸州红1号2个高粱品种在移栽前7 d、移栽前、移栽成活后和中耕期进行除草处理,观察3种除草剂在不同施用时期的除草效果及对高粱生长和产量的影响。[结果]除在移栽成活后、中耕期施用农达有强药害外,其余各处理基本无药害,除草效果以农达最好,史它隆仅对宽叶杂草效果较好,38%琇去津药效较慢。相对于清水对照,在移栽前7 d施用农达、移栽成活后施用38%琇去津对杂交和常规高粱的产量及其生长性状的增加效应最明显。[结论]为高粱地杂草的防治提供了理论依据。

[目的]比较几种除草剂的除草效果。[方法]以甜高粱杂交种“天青一号”为供试作物，防效和株高为指标，通过苗前、苗后大田药效试验，研究几种除草剂的除草效果及对甜高梁的安全性。[结果]在该试验条件下，除草剂莠去津在播后苗前用药量为6．000kg／hm2时防效较好，而在苗后用药量为10．390kg／hm2时防效为佳，并且苗后比苗前用药的除草效果要好。不同除草剂在苗后同一施药时期防除杂草的效果不同。38％莠去津防效均高于72％乳油2，4．滴丁酯和48％排草丹，总防效达到94．7％，且对杂交甜高粱生长影响最小，苗后1次用药即可取得比较理想的除草效果。[结论]该研究为甜高粱地杂草的防治提供了科学依据。

为解决山西省高粱田杂草防除难的问题,采用完全随机区组的试验方法进行了山西省高粱田土壤封闭剂和茎叶处理剂的筛选研究。结果表明：播后苗前土壤处理,莠去津、金都尔和2,4-D丁酯单剂用量分别在6750、1350、1200 m L/hm^2以下时,高粱出苗安全且除草效果好;莠去津和金都尔复配组合最优配比为5250 m L/hm^2＋900 m L/hm^2。苗后茎叶处理,除草单剂二氯喹啉酸、莠去津、二甲四氯、2,4-D丁酯除草效果较好且对高粱产量影响较小,使用剂量分别为750 g/hm^2、2700 g/hm2、1500 g/hm^2、1050 m L/hm^2;复配剂最优配比为莠去津2250 g/hm^2＋二氯喹啉酸600 g/hm^2、莠去津2250 g/hm^2＋2,4-D丁酯300 m L/hm^2和苯达松3000 m L/hm^2＋二氯喹啉酸750 g/hm^2。

本研究采用室内整株生测法测定了新型除草化合物二氯喹啉草酮的杀草谱、除草活性及对不同水稻品种的安全性。二氯喹啉草酮600 g/hm2,a.i.处理对秋熟杂草无芒稗、稗草、西来稗、光头稗、硬稃稗、马唐、鳢肠、陌上菜、丁香蓼、异型莎草、碎米莎草地上部分鲜质量抑制率均高于90%,对耳叶水苋、鸭舌草地上部分鲜质量抑制率低于80%,对千金子地上部分鲜质量抑制率低于50%;对夏熟杂草猪殃殃、牛繁缕、荠菜、大巢菜地上部分鲜质量抑制率均低于90%,而对日本看麦娘、看麦娘、菵草、硬草、棒头草、早熟禾、野燕麦和野老鹳草地上部分鲜质量抑制率均低于30%。二氯喹啉草酮对主要秋熟杂草无芒稗、稗草、西来稗、光头稗、硬稃稗、马唐、鳢肠、陌上菜、丁香蓼、异型莎草和碎米莎草的ED90值为214.872 0~489.547 8 g/hm2,a.i.。二氯喹啉草酮在水稻和秋熟杂草硬稃稗、西来稗、无芒稗、稗、光头稗、马唐、鳢肠、陌上菜、异型莎草、碎米莎草间的选择性指数较高,为6.16~16.47。二氯喹啉草酮对多种恶性秋熟杂草防效好,且对水稻安全,在水稻田应用前景广阔。

The current widely used grain sorghum hybrid Liaoza No.10 was chosen as test materials. The effect of different concentrations herbicides of Atrazine, Metolachlor, 2,4 D Butyl ester, Acetochlor and their compounds on the emergence, photosynthetic rate and dry matter accumulation were compared and analyzed. The results showed that for the preemergence treatment, when the concentration of Atrazine, Metolachlor, 2,4 D Butyl ester, and Acetochlor are lower than 6 750, 1 050, 900 and 750 mL/hm individually using preemergence treatment, there are less impact on sorghum emergence and good effect of weeding. At 5 leaf stage, complex combination of X15 with Atrazine, Acetochlor and 2,4 D Butyl ester (3 750 mL/hm+600 mL/hm+750 mL/hm), and complex combination of Atrazine, 2,4 D Butyl ester and Metolachlor of X20 (4 500 mL/hm+975 mL/hm+675 mL/hm) could ensure high emergence rate, relatively low seedling damage and has advantages over a single herbicide. For the postemergence treatment, recommended herbicide applying time is after the 5 leaf stage if it is under the premise of weeds controllable. The sensitivity of seedlings to each herbicide under the designed dosage in this study is: Acetochlor> (Atrazine + 2,4 D Butyl ester + Acetochlor)> trazine +2,4 D Butyl ester + Metolachlor > Metolachlor > 2,4 D Butyl ester > Atrazine. The decline of net photosynthetic rate is the important reason for the higher seedling damage rate, it also causes the opposite trend between dry matter accumulation and sensitivity of seedlings to herbicide.

农田杂草的危害是阻碍农业生产快速、健康发展的主要因素之一。农田杂草的发生受到诸多自然因素的影响和人工措施的调控,而作物格局、土壤耕作和水肥管理是除施用除草剂外最基本的人工干扰措施。本文综述了作物种类和时空格局对杂草的影响,阐述了主要的作物种植模式防治杂草的效果,并比较了不同土壤耕作和水肥管理措施下杂草群落的变化,重点剖析了杂草发生的调控机制,探讨了通过作物与杂草的资源竞争、作物的他感作用及土壤种子库的变化来调控杂草发生的可能机理。综合相关研究发现,合理的轮作和间混套作表现出对田间杂草明显的抑制作用;免耕可以增加杂草的群落多样性,秸秆覆盖能降低杂草密度和生物量;施肥对杂草的影响因作物种类、施肥量和肥料类型等不同而不同,长期均衡施肥能降低杂草密度,增加杂草群落多样性;灌溉和提高自然降水利用效率能抑制旱地杂草,特定时间进行深水管理能够有效控制某些水田杂草。最后,针对目前研究和实践中的具体问题,展望了未来一段时间杂草的研究方向和应用前景。