Allelopathy of Aerial Part Extracts from Grafted Eggplants

[ Objective] The aim was to provide evidence and countermeasures for study on allelopathy of eggplant and supply a scientific basis for ecological management of allelopathy and establishment of a reasonable, effective intercropping and continuous cropping system. [ Method] Allelopathy of aerial part extracts from grafted eggplants was studied by bioassay. [ Result] The results showed that aerial part extracts of eggplants have autotoxiclty which inhibited seed germination and seedling growth of eggplants. Aerial part extracts of grafted eggplants inhibited seed germination and seedling growth of tomato, pepper and cu cumber at different level. Inhibition intensity of extracts was in order of tomato 〉 pepper 〉 cucumber. The inhibition effect was higher at 0.2 g/ml concentration than 0.1 g/ml concentration. There wasn＇t significance between ownrooted treatments and grafted treatments. [ Conclusion] Eggplant is not suitable for round of inter-cropping with tomato, pepper and cucumber.

Allelopathy Effect of Wheat Root Aqueous Extracts on Different Vigna angularis Varieties

Objective] This study aimed to investigate the al elopathy effect on the seed germination and seedling growth of different adzuki bean （Vigna angularis） vari-eties in wheat root aqueous extracts. [Method] Culture dish method and pot experi-ment were carried out with the seeds and the seedling of 10 adzuki bean varieties, respectively, and seed germination rate and various indexes of the seedlings were measured. [Result] ① 30 g/L wheat root aqueous extracts very significantly im-proved the germination rate and sprouting index of B1789, Baihong 3, Baohong 947. ② The genotype differences of adzuki bean seedling was presented by the morphological index in wheat root aqueous extracts treatment; among al the mor-phological indexes, Baohong 947, Jinhong 3 presented a positive al elopathic effect, and their plant height, root length and leaf area were extremely significantly in-creased, while the fresh weights of both above-ground and underground parts were increased obviously, compared with the control. ③ According to the synthetical al-lelopathic indices, wheat root aqueous extracts had different degrees of promoting effects on the six adzuki bean varieties： Baohong 947〉Baihong 6〉B1789〉Zunhua-hong〉Jihong〉Jinhong 3〉Baohong 8824-17〉Baihong 3. ④ Treated by wheat root aqueous extract, the SOD activity, POD activity, MDA content, TTC activity and chlorophyl content in the seedlings of adzuki beans of different genotypes changed by a smal er range in al elopathic promotion varieties than in al elopathic inhibition varieties. [Conclusion] The results proved that Baohong 947 is the best summer-planting variety after wheat.

强力消毒灵对口蹄疫病毒的杀灭效果试验

以２～３日龄乳鼠为靶动物，以猪口蹄疫病毒及猪水泡病毒感作液给其染毒，观察了强力消毒灵对两种病毒的杀灭效果，并以英国产“农福”作对照，结果表明，两种消毒剂对上述两种病毒均有较强的杀灭作用，但强力消毒灵优于农福，前者的最高稀释倍数为１∶８００，后者为１∶２００。

Allelopathic Effect of Adzuki Bean Root Aqueous Extracts on Four Crops

For choosing suitable summer-planting adzuki bean crop, this experiment adopted the method of indoor petri dish bioassay to study the allelopathy effect of adzuki bean, radish, cabbage and wheat under different concentrations of adzuki bean root aqueous extracts. The result showed that the adzuki bean had a strong inhibition towards its germination rate and germination index. With the increasing concentration of the adzuki bean root aqueous extract, the seed germination rate and germination index of the three kinds of receptor crops presented a decreasing trend. From the root length, spire length, the number of lateral roots, plant height, fresh mass and other morphological indexes of seedlings, it was concluded that with the increase of concentration of adzuki bean root aqueous extract, only wheat pre- sented a promotion effect while the other two kinds of receptor crops showed an inhibition effect, which were not significant at low concentrations. With the increase of concentration of adzuki bean root extracts, the SOD and POD activities of radish and wheat also increased, while the two kinds of enzyme activities of cabbage showed a decreasing trend. The MDA contents in seedlings of radish and wheat decreased, while the MDA content in cabbage increased significantly, which showed that wheat could be used as a rotation crop of adzuki bean, and radish also had a great application potential in adzuki bean crop rotation.

Studies on the Allelopathic Potential of Corn （Zea mays L.） Aqueous Extracts and Root Exudates

This investigation was carried out at Faculty of Agriculture and Forestry-University of Duhok/Kurdistan-Iraq. Three experiments were included in this investigation： （1） First experiment was a bioassay related to the germination performance, shoot and root development of corn （Zea mays L.） and peanut （Arachishypogaea） at two concentrations of root （3% and 1.5%） and shoot （12% and 6%） aqueous extracts of corn medium; （2） The second experiment dedicated to the intercropping of corn and peanut at four treatments; （3） While the third experiment involved the effect of peanut root exudation on growth of corn. Experiment results revealed that corn shoot and root water extracts highly inhibited seed germination of both corn and peanut, the inhibitory of shoot extract was more than root aqueous extract. While its effect on the seedling growth was vice versa as compared with control treatment, there was an increase in root and shoot length of both corn and peanut when grown in corn aqueous extracts. Intercropping experiment results has stimulated most traits of peanut under studying. Also for corn, there was apparent and significant increase in all characteristics as compared with control. It was further confirmed from the results of peanut root exudates that had all studied characters of corn were stimulated than the control treatment.

Cavitation field from a horn—A new model

The cavitation field from a horn-type transducer is experimentally probed by the optical method.Based on these observations,we propose a model of the field which hypothesizes that most violent caviation bubbles originate from the vibrating surface and there-from fast drift to the near liquid region.These bubbles are chiefly responsible for the practical applications of cavitation for a large power input to the transducer.During migration they become weakened.Cavitation bubbles are also produced in the liquid region by the acoustic wave directly emitted by the transducer,but these bubbles are weak due to the shielding effect of the bubbles clinging to the transducer vibrating surface.Consequently,only weak cavitation bubbles exist in the far liquid region.