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91.
Summary

The establishment of the optimum plant population has been shown to be one of the most crucial determinants of the marketable yield of bulbous crops. This study was conducted to determine the best plant arrangements for maximum yields and maximum bulb quality in rainfed garlic (Allium sativum L.) grown under Mediterranean conditions. The effects of row width and plant spacing on the yield and quality of the two cvs. Morado de Pedroneras and Germidour, were investigated on Córdoba, Spain, in Vertisol Chromoxerert soil. In 1987–1988, a wet growing season, higher yields and higher bulb quality were obtained than in 1988–1989; cv. Germidour yielded more per unit of land area of higher quality bulbs during both seasons. Narrow row width and/or narrow plant spacing resulted in higher values of dry matter, LAI, LAD, CGR and yield, whereas wide row spacing and/or wide plant spacing resulted in higher ware-sized bulb yield. LAD was closely related to yield (r2 = 0.96**) and total dry matter (r2 = 0.90**). Mean leaf surface was affected by plant density and climatic conditions and showed a high positive relationship (r2 = 0.90**) with the percentage of Extra grade of bulbs (>50 mm). As a result of this study, a row width of 45–60 cm with plant spacing of 12–16 cm is recommended for cv. Germidour and 45 × 16 cm for cv. Morado, to maximize the proportion of high-quality yield under Mediterranean rainfed cropping systems.  相似文献   
92.
93.
As there was no consensus on the presence or absence of Aphis (Toxoptera) citricidus (Kirkaldy) in Chile, a meticulous literature survey has been carried out to clarify the issue. From this survey, it can be concluded that A. (T.) citricidus is not present in Chile, that it has never been cited as present from first‐hand information/observations in this country, and that all available Chilean records of this species are due to old (and now abandoned) taxonomic interpretations or poor transmission of information.  相似文献   
94.

Purpose

The traditional method to determine humic content (humic and fulvic acids) in commercial fertilizers, biostimulants, and organic materials is based on the oxidation of the organic carbon contained in the basic-soluble but acid-insoluble fraction (humic acids) and the basic-acid soluble fraction (fulvic acids) of their alkaline water extracts. This methodology, merely operational, makes it impossible to distinguish if the quantified carbon corresponds to substances with “humic” chemical nature or to non-humic organic matter but with similar solubility properties to those of humic matter. The aim of this work is to develop a new methodology that not only quantifies the humic content in commercial products (and raw materials) but also assesses the humic quality of the quantified organic matter.

Materials and methods

To this end, humic and fulvic (-like) fractions have been isolated/purified from several humic and non-humic materials and characterized by means of elemental analysis and UV-visible, fluorescence, and infrared spectroscopies, and these data have been used to perform a discriminant analysis (DA).

Results and discussion

The model obtained from the DA is able to discriminate humic and fulvic fractions from apparently humic or fulvic ones and provides discriminant classification functions that have proven to successfully predict the “humic quality” of the fractions isolated from commercial products, after their elemental and spectroscopic characterization.

Conclusions

Therefore, the combination of the fractionation, characterization, and evaluation by the DA is proposed as an effective methodology for quantifying and assessing the quality of the humic content claimed in the labels of commercial products.
  相似文献   
95.
96.
Sheep were medicated with progestogen sponges, pregnant mare's serum gonadotrophin, naloxone or nalbuphine during April, May, June or September 1986. It was observed that when suckling ewes were treated three or five weeks post partum with 45 mg medroxyprogesterone acetate (incorporated on an intravaginal sponge) for 12 days followed by 500 iu of pregnant mare's serum gonadotrophin and 0.4 mg naloxone administered intramuscularly after the withdrawal of the sponge, oestrus became evident 24 to 48 hours after the sponges were withdrawn. However, when the naloxone was replaced by 10 mg nalbuphine administered intramuscularly, oestrus was not shown. When the ewes were medicated with the same combination of drugs during anoestrus, the result was similar to that observed during lactation and oestrus was displayed only in the ewes that received naloxone. Thus the opioid antagonist naloxone facilitates the expression of oestrus in the ewe during anoestrus and lactation.  相似文献   
97.
A double-blind, randomized, placebo-controlled study was conducted to examine the effect on heart failure class and survival of pimobendan, an oral calcium-sensitizing inodilator, in dogs with dilated cardiomyopathy (DCM). Pimobendan (0.3-0.6 mg/kg body weight/d) or placebo was administered to English Cocker Spaniels (CSs; n = 10) and Doberman Pinschers (DPs: n = 10) that had DCM in addition to background therapy of furosemide, enalapril, and digoxin. Addition of pimobendan to standard triple therapy was associated with a significant improvement in heart failure class, regardless of breed (P < .02, Mann-Whitney rank sum test). Overall, 8 of 10 animals in the pimobendan-treated group, and 1 of 10 animals in the placebo group improved their heart failure status by at least I modified New York Heart Association functional class after initial stabilization (P = .005, Fisher's exact test). Pimobendan had no significant effect on survival in the CSs (P = 0.77, log-rank test), but DPs treated with pimobendan had significantly longer survival times compared with placebo (P < .02, log-rank test), with a median survival time of 329 days in the pimobendan group compared with 50 days in the placebo group, and a hazard ratio of 3.4 (95% confidence interval 1.4-39.8). Pimobendan resulted in significant improvement in heart failure class when added to standard therapy in this group of dogs with DCM, and may have contributed to improved survival in DPs.  相似文献   
98.
Tropical Animal Health and Production - The objective of the study was to assess the effects of water deprivation on the burden of gastrointestinal nematodes in Nguni does. A survey was piloted on...  相似文献   
99.
100.
Seroprevalence of Toxoplasma gondii was tested for in 585 cats in different regions of Spain. Sera were tested by the indirect immunofluorescence antibody test (IFAT). Specific antitoxoplasma IgG (IFAT titer>or=1/80) were found in 189 of 585 (32.3%): 117 of 317 (36.9%) stray cats, 16 of 48 (33.3%) farm cats and 56 of 220 (25.5%) household cats. The overall prevalence was significantly higher in stray groups (36.4% of 365) than in household cats (25.5% of 220), higher in adult cats (>6 months old, 36.8% of 443) than in juvenile cats (<6 months old, 13.9% of 101), and higher in male stray cats (45.3% of 128) than in female stray cats (32% of 153). Prevalence of intestinal parasites was also analysed by a routine coprological method in 382 of the 585 cats. Intestinal parasites were found in 107 faecal samples (28%): 76 of 231 (32.9%) stray cats, 14 of 48 (29.2%) farm cats and 17 of 103 (16.5%) household cats. T. gondii oocysts were not found in any faecal samples analysed. The following prevalences of other intestinal parasites were found: Toxocara cati (18.3%), Toxascaris leonina (1.3%), Ancylostoma sp. (1%), Capillaria spp. (1.3%), Aelurostrongylus abstrusus (1%), Taenia like (3.7%), Dipylidium caninum (2.6%) and Cystoisospora spp. (6.3%).  相似文献   
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