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81.
82.
Mature papaya fruits were stored at 10 and 15°C to study the effect of these temperatures on the storage and of respirational activity during storage. Percentage weight loss of fruits increased with prolonged storage period, and the increase was greater in fruits stored at 15 than at 10°C. The decay percentage was greater at the higher temperature than at the lower temperature. Total soluble solids showed a slight and gradual increase upto the end of the storage period. The high storage temperature accelerated colour development in the peel and total chlorophyll diminished. There was an increase in total carotenoids in both the peel and the pulp as the storage period increased, and the rate of increase was greater at the higher temperature.The respiration rate was relatively low at the beginning of ripening and tended to level off until the 11th and 12th day of storage, which were followed by a striking increase until it reached its maximum rate at the over ripe stage.  相似文献   
83.
84.
A 10-year-old spayed domestic shorthaired cat was presented for behavioural changes, signs suggestive of visual deficits and aimless circling. Neuro-ophthalmological examination suggested the cat had central blindness. CT scans following administration of iohexol demonstrated a contrast-enhancing mass in the vicinity of the third ventricle resulting in obstructive hydrocephalus. Following rostral tentorial craniotomy and incision through the cerebral cortex, the third ventricle was approached via the dilated left lateral ventricle. An ependymoma was seen through a dorsocaudolateral incision into the third ventricle, and removed by gentle manipulation and suction. The cat recovered unremarkably, regaining normal vision and behaviour.  相似文献   
85.
An area of 50 feddans cultivated with soybeans was treated withBacillus thuringiensis (B.t.) baits againstAgrotis ypsilon and 60 feddans were sprayed withB.t. spray againstSpodoptera littoralis. WhenB.t. baits were used, the percentage of kill ofA. ypsilon reached 96.1–96.4% compared to 97.4–98% kill on using hostathion baits. WhenB.t. was sprayed againstS. littoralis, a percentage of larval kill 88.3% was obtained. This increased to 97.3% after the second application. On the other hand, the precentage of kill reached 96.8% when lannate was sprayed once. The average yield was 1.54 tons/fed. whenB.t. was sprayed twice againstS. littoralis and 1.42 tons/fed. when sprayed once. Areas, treated with lannate gave 1.44 tons/fed., while in the untreated area the yield was comparatively low being 0.83 tons/fed.Mith 4 tables  相似文献   
86.
The mechanism of resistance to quinclorac was investigated in a smooth crabgrass biotype [Digitaria ischaemum (Schreb. ex Schweig) Schreb. ex Muhl] from Tulare County, California. Quinclorac (8.96 kg a.i. ha−1) had no effect (P = 0.18) on the resistant (R) biotype, but reduced fresh weight of a susceptible (S) biotype by 93%. After treatment with 4.48 kg a.i. quinclorac ha−1, the S biotype produced about three times more ethylene than the R biotype and accumulated cyanide in tissues. Similar amounts of endogenous cyanide resulting from treatment with KCN reproduced quinclorac phytotoxicity. Pre-treatment with the ACC synthase inhibitor AVG reduced quinclorac phytotoxicity by 37% and ethylene production by 89%. These data suggest a target site-based mechanism of resistance involving stimulation of ACC synthesis and accumulation of cyanide. Also, the R biotype had four times more β-cyanoalanine synthase activity than the S biotype, suggesting a higher ability to detoxify cyanide.  相似文献   
87.
Pot experiments were carried out to explore the role of macrochilid mites,Macrocheles muscaedomesticae (Scop.), and staphylinid beetles,Philonthus longicornis Steph. and collembola,Onychiurus sp. singly and in combination onTylenchulus semipenetrans (Cobb) on sour orange at 29±5°C 74±5% R. H. in green house. All tested soil mesofauna significantly reduced the population of the nematode. The highest predation rate was achieved by the predator mite,M. muscaedomesticae (Scop.) singly, followed by the combination of soil mite plus collembola. The numbers of soil mesofauna recovered from soil at the end of the experiment were significantly higher in treatments of nematode plus one of each of soil mesofauna than monoinoculation of each.  相似文献   
88.
The predacious miteAgistemus exsertus Gonzalez was reared in the laboratory on the eriophyid miteAculops lycopersici (Massee) for studying the development, fecundity and predation efficiency. At 30°C and R.H. 75% the duration of the predator egg incubation, immature stages, life cycle, oviposition and longevity of the adult female was 0.92, 2.10, 3.02, 4.89 and 7.20 days respectively in average. The consumption by one adult female ofA. exsertus per day on the different stages of the eriophyid miteA. lycopersici was 60.3 eggs and 45.3 immature and mature stages.  相似文献   
89.
The relation between the pathogenBacillus thuringiensis and the predatorOrius albidepennis (Hem.: Anthocoridae) associated with the greasy cutwormAgrotis ypsilon (Lep.) has been investigated. The biology of the predator showed to be affected in terms of nymphal duration, rate of food consumption and egg production when the predator larvae were fed on treated eggs or neonate larvae of the host (A. ypsilon). The effect of B-exotoxin (thuringiensin) on the predator has been also demonstrated.  相似文献   
90.
Anthelmintic resistance (AR) is a well-recognized challenge in farmed ruminants. The use of anthelmintics in combination is one of the strategies recommended to slow the rate of AR development. Two studies were undertaken in 2017 and 2019 to assess the efficacy of single-dose macrocyclic lactone (ML) anthelmintic and ML combination drenches. In total, 11 Faecal Egg Count Reduction Trials (FECRTs) were set up in 10 different beef herds, with results available from 10 of those FECRTs (9 herds). AR to a single ML anthelmintic was detected in all 9 herds, with resistance to Cooperia and Haemonchus spp on 9 farms, and resistance to Ostertagia and Trichostrongylus spp on 2 farms. In contrast, for the ML combination anthelmintics, all FECRTs resulted in efficacies of 99%–100%. The results suggest that cattle producers should strongly consider using combination drenches in their herds in preference to single actives.  相似文献   
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