The effect of some herbicides on lactate dehydrogenase activity

The effect of herbicides N-(phosphonomethyl)glycine (glyphosate), 2-methyl-4-chlorophenoxyacetic acid (MCPA), 2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine (atrazine) and the respective commercial preparations “Round-up”, “Aminex”, and “Zeazin”, on the activity of lactate dehydrogenase isolated from germinating soybean seeds and beef heart were compared. The main aim of the work was to compare the effect of the herbicides on lactate dehydrogenase isolated from animal and plant material. Simultaneously the effect of herbicides and the respective commercial preparations was compared. Substantial differences resulting from the two comparisons indicate differences in the structure of active centres of lactate dehydrogenase isolated from animal and plant material, and also a considerable effect of additives and surfactants in commercial preparations.     

The effect of herbicides on the root system of wheat plants

Three commercial herbicides, at the rates normally recommended for selective weed control in cereal crops, deformed the roots of spring wheat plants grown in sand culture. Affected roots produced large numbers of short swollen lateral branches which later grew on to form tassel-like bundles of side roots. Only the mecoprop and MCPA components of the mixtures were responsible for the deformities; ioxynil and dicamba had no effect. Mecoprop applied to the rooting medium severely deformed the roots but foliar application also resulted in some abnormalities. The effects of the herbicides on root and shoot dry weights were not correlated with their deformative effects.     

The effect of microorganisms on phytotoxicity of herbicides. III. Interaction of Bacillus sp. 72 with Venzar.

Interactions between Venzar and some metabolites of Bacillus ps. 72 were studied. This strain was found to produce flavonoids increasing the phytotoxicity of Venzar. Venzar action was also increased by NH4+ ions released aboundantly by the bacterial strain.     

几种除草剂对入侵生物少花蒺藜草的防治效果

【背景】2009~2012年辽宁省草原沙化治理工程在辽西北展开,以彰武县为重点治理地区。由于长期缺乏对草原毒害草的重视,少花蒺藜草在彰武县全县范围内扩散蔓延,并已发展到难以控制的局面,给草原生态环境带来极大影响。【方法】对精喹禾灵、烯禾啶、咪唑乙烟酸、烟嘧磺隆、乙草胺＋烟嘧磺隆、乙氧氟草醚、高效氟吡甲禾灵等几种除草剂（组合）进行筛选,并进行大面积示范,调查其防治效果。【结果】供试的7种药剂（组合）对少花蒺藜草均有一定的防除作用。其中,精喹禾灵和高效氟吡甲禾灵2种芳氧苯氧基丙酸酯类除草剂防除入侵生物少花蒺藜草效果最为理想,能够有效控制其生长和危害,施药15 d后防除效果分别可达到89%和79%。此外,药剂筛选试验结果还显示：咪唑乙烟酸、烟嘧磺隆和乙草胺＋烟嘧磺隆对少花蒺藜草也有较好的防治效果,施药19 d后防效基本达到80%以上;乙氧氟草醚最差,防治效果只有66%。【结论与意义】5%精喹禾灵乳油除草效果较好,虽然对试验区内的其他禾本科牧草有一定的杀害作用,但对区内的补播牧草草木樨、小叶锦鸡儿等未产生任何药害。这对草原补播改良区少花蒺藜草的综合治理有着积极意义。     

The analysis of the effect of different herbicides on Johnson-grass in maize

The Johnson-grass (Sorghum halepense /L./Pers) is a perennial monocotyledon, its gen centre is in the Near East. Botanically this weed belongs to the monocotyledone class, Poaceae (Gromineae) family and within this, together with the maize to the Andropogonoideaei subfamily. At the time of the First National Weed Survey (1947-1953) it has not been found in Hungary. In the periods of the 2nd (1969-1971), 3rd (1987-1988) and 4th Survey it occupied the 94th, 18th and 10th place of importance, respectively. Because of its rapid multiplication and spreading after the second weed survey (1969-1971) and because of its very complicated and difficult control, the Plant Protection Division of our Ministry of Agriculture ranged it in 1974 into the category of "Dangerous weed". Johnson grass is the 6th most important weed in the world. A small plot field trial was carried out in Szabadszentkirtly (12th May 2006) in maize. The effect of pre- and post emergent herbicides was investigated against Johnson grass germinating from seed and sprouting from rhizome. The treatments were done in 4 repeats with Stomp 330 EC, Dual Gold 960 EC, Merlin WG, Wing EC, Guardian Max and Monsoon herbicides. The number of weeds germinating after spraying and the number of damaged weeds were counted and compared to the control plots 10 days after the treatments and then weekly. Parallel to the field trial, a "soil culture in pots" trial in glasshouse was also carried out in which the effect of the above mentioned herbicides was investigated against Johnson grass germinating from seed. During on experiments all the herbicides showed an excellent herbicide activity until the 2nd week of treatment, although the precipitation of the second week was only 8.4 mm. Under the given experimental conditions the best herbicide effect until the 4th week, in both experimental phases were given by Merlin WG.     

The influence of some herbicides on selected groups of microorganisms in loess and sandy soils. II. The effect of nitrification.

Studies on the effect of herbicides on nitrification in field and laboratory conditions have shown that steady use of these substances in the same field does not exert a significant effect on this process in the soil. The herbicides caused only shortlasting disturbances. Nitrification usually returned to a relative equilibrium in several days after the herbicide application.