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221.
An examination of the blood profile of domestic fowls infected with Raillietina echinobothrida revealed anaemia with a significant increase of total leukocyte counts and decrease of total serum protein. The pathological changes in the intestines were characterised by villous atrophy, enteritis with cellular infiltration and formation of characteristic granulomas. 相似文献
222.
Spray deposit patterns on simulated and live foliage of balsam fir and white birch were determined at different heights and at periphery and interior locations of the tree crown, following aerial and ground applications of fenitrothion formulations over a boreal forest near Searchmont, Ontario. Droplet size spectra and AI deposits were assessed at ground level with ‘Kromekote’ card/glass plate units. Aerial application was made with a Cessna 188 aircraft fitted with ‘Micronair’ AU3000 atomizers. For ground application, a ‘Soloport’ 423 backpack mistblower fitted with an extension tube and a diffuser nozzle at the tip was used. Deposit data on the ground samplers indicated significantly larger droplets and greater deposits from the aerial spray trial than from the mistblower treatment. However, foliar deposits at tree canopy level were only slightly higher in the former trial than in the latter. Analysis of spray deposits on simulated and live fir foliage showed definite gradients in deposit levels, decreasing from top to bottom crown, and from periphery to inner tree crown. In the birch tree crown, such gradients were not observed. The simulated leaves generally acted as better collectors of spray droplets than the natural leaves. The overall mean deposit values, expressed in ng cm?2, showed a wide variation, although there was generally a close relationship between the deposits on the simulated and natural surfaces. 相似文献
223.
Archana Verma R. Kaushal N. M. Alam H. Mehta O. P. Chaturvedi D. Mandal J. M. S. Tomar A. C. Rathore Charan Singh 《Agroforestry Systems》2014,88(5):895-905
Grewia optiva Drummond is one of important agroforestry tree species grown by the farmers in the lower and mid-hills of western Himalaya. Different models viz., monomolicular, logistic, gompetz, allometric, rechards, chapman and linear were fitted to the relationship between total biomass and diameter at breast height (DBH) as independent variable. The adjusted R2 values were more than 0.924 for all the seven models implying that all models are apparently equally efficient. Out of the six non-linear models, allometric model (Y = a × DBH b ) fulfils the validation criterion to the best possible extent and is thus considered as best performing. Biomass in different tree components was fitted to allometric models using DBH as explanatory variable, the adjusted R2 for fitted functions varied from 0.872 to 0.965 for different biomass components. The t values for all the components were found non-significant (p > 0.05), thereby indicating that model is valid. Using the developed model, the estimated total biomass varied from 6.62 Mg ha?1 in 4 year to 46.64 Mg ha?1 in 23 year old plantation. MAI in biomass varied from 1.66–2.05 Mg ha?1 yr?1. The total biomass carbon stocks varied from 1.99 Mg ha?1 in 4 year to 15.27 Mg ha?1 in 23 year old plantation. Rate of carbon sequestration varied from 0.63–0.81 Mg ha?1 yr?1. Carbon storage in the soil up to 30 cm soil depth varied from 25.4 to 33.6 Mg ha?1. 相似文献
224.
ABSTRACT Field experiments were carried out for three consecutive years (2003–2006) at Bangladesh Sugarcane Research Institute farm soil on plant (first crop after planting) and subsequent two ratoon crops of sugarcane. The main objectives of the study were to assess the direct and residual effects of organic and inorganic fertilizer on growth, yield, and juice quality of plant and ratoon crops. The plant crop consisted of four treatments. After harvesting of plant crop to evaluate the residual effects on ratoon crop the plots were subdivided except the control plot. Thus, there were seven treatments in the ratoon crop. Application of recommended fertilizer [nitrogen (N150), phosphorus (P52), potassium (K90), sulfur (S35), and zinc (Zn3) kg ha? 1] singly or 25% less of it either with press mud or farmyard manure (FYM) at 15 t ha? 1 produced statistically identical yield ranged from 67.5 to 69.0 t ha? 1 in plant crop. In the ratoon experiment when the recommended fertilizer was applied alone or 25% less of its either with press mud or FYM at 15 or even 7.5 t ha? 1 again produced better yield; it ranged from 64.8 to 69.2 in first ratoon and 68.2 to 76.5 t ha? 1 in second ratoon crops. Results showed that N, P, K, and S content in leaf progressively decreased in ratoon crops over plant crop. Juice quality parameters viz. brix, pol, and purity % remained unchanged both in plant and ratoon crops. Furthermore, organic carbon (C), available N, P, K, and S were higher in post harvest soils that received inorganic fertilizer in combination with organic manure than control and inorganic fertilizer treated soil. It may be concluded that the application of 25% less of recommended fertilizer (N112, P40, K68, S26, and Zn2.2.5 kg ha? 1) either with press mud or FYM at 15 t ha? 1 was adequate for optimum yield of plant crop. Results also suggest that additional N (50% extra dosage) keeping all other fertilizers at the same level like plant crop i.e. N168, P40, K68, S26, and Zn2.25 kg ha? 1 either with press mud or FYM at 7.5 t ha? 1 may be recommended for subsequent ratoon crops to obtain good yield without deterioration in soil fertility. 相似文献