To elucidate the inheritance of seed coat color in
A pot experiment was conducted in a glasshouse to investigate the correlation between specific fine root length (SFRL) and root colonization (RC) of maize inoculated with six arbuscular mycorrhizal fungi (AMF) in three soil types. The results showed that six AMF associated with maize presented different abilities in RC and effects on SFRL. In addition, there was a significant correlation between SFRL and RC of arbuscular mycorrhizal maize in Beijing soil (Cinnamon soil), but no significant correlation in Hubei soil (Brunisolic soil) and Guangdong soil (Red soil). It is concluded that mycorrhizal colonization decreased the SFRL of maize, and the correlation between SFRL and RC of mycorrhizal maize depended on soil type.
The strains capable of resistance against
The development process and morphology of the microspores in Chinese kale and false pakchoi were observed by using the whole stain-clearing technique. The results showed that the morphological characteristics of microspores were not only extremely similar, but were also in their development processes. The microspores at tetrad stage showed an arrangement of tetrahedral type, and after being released and passing through two mitoses, they developed gradually to form rotundly-shaped mature pollen grains containing three nuclei, one bigger alimentation nucleus and two smaller similar-sized generative nuclei. Determination of bud sizes at four typical microspore developmental stages revealed that the bud size had a stable heredity at each development stage of the microspores. The ratio of the bud length at the late uninucleate stage to the largest bud length differed little between Chinese kale and false pakchoi, ranging from 0.37 to 0.45 with an average of 0.41, though there was significant difference among their cultivars. It was concluded that the length of buds at late uninucleate stage can be estimated for undetermined cultivars of these two
This study was conducted to develop weed-suppressing rice varieties in a weed-suppressing nursery by specific secondary metabolite markers of allelopathic potential. Weed-suppressing rice variety Feng-Hua-Zhan was screened out by a specific secondary metabolite marker of allelopathic potential. Weed-suppressing rice No.1, a new rice line with good quality, was also developed using this method. The genetic backgrounds and research directions of weed-suppressing rice varieties are discussed in this paper.
Effects of hydroxybenzoic acid, an important autotoxic substance in roots, on plant growth, photosynthesis and
The essential oil from the leaves of yacon grown in China was isolated by hydrodistillation and distillation-extraction. Chemical constituents of the essential oil were separated and identified by means of gas chromatography/mass spectrometry (GC/MS) for the first time, and the relative content of each constituent was determined by area normalization. Twenty-one chemical constituents were identified, and their amounts accounted for 96.2% of the total composition. The main components of the essential oil were β-phellandrene (26.3%), β-cubebene (17.7%), β-caryophyllene (14.0%) and β-bourbonene (10.2%). Therefore, in the volatile oil from the leaves of yacon, sesquiterpenes are major compounds, accounting for 52.2%.
Site-directed mutagenesis is used extensively for probing gene function. In this paper we describe an improved megaprimer method to the site-directed mutagenesis of phytase from
Significant progress has been made over the past several years in the understanding of phosphorus (Pi)-starvation responses in plants and their regulation. The transcriptional changes that occur in response to Pi starvation are beginning to be revealed, although much is left to understand about their significance. In this paper, the recent progresses on the gene expression changes under deficient-Pi, cis-regulatory elements involved in response to deficient-Pi, the transcriptional control of Pi-starvation responses in eukaryotes, transcription factors involved in response to Pi-starvation, the role of MicroRNA on regulation of phosphate homeostasis, and phosphate sensing and signal transduction in plants have been summarized. The purpose of this review is to provide some basis for further elucidation of the transcriptional responses and regulations, and the networks of Pi sensing and signal transduction under deficient-Pi in plants in the future.
An ethylene receptor
The pear (
The major incompatibility barriers to specific inbred lines and the long generation duration in
Effects of solar radiation, rainfall and cultivars on “imperfect shell development” (ISD) of the thin-shelled walnut were studied by means of field investigation and weather data comparison. The results showed that cultivars were the main factor causing the ISD of the thin-shelled walnut. Among the cultivars, Shangsong 6 was the most sensitive one, whose percentage of imperfect shell attained 67.3%, followed by Xiangling (52.7%). However, the rate of imperfect shells in Zhonglin 5 was only 20.9%. It was suggested that the main environmental factors contributing to the ISD of the thin-shelled walnut were sunlight intensity and rainfall during the shell-hardening stage.
Cadmium (Cd) is a toxic environmental pollutant with a long biological half-life and can produce both hepatic and renal injuries in mammals and fish. Squid viscera meal (SVM), an effective attractant for aquatic animals, is widely used as an ingredient in aquafeeds. However, SVM is rich in Cd and its complexes. A study was conducted to evaluate the effects of dietary SVM on the growth and Cd deposition in the tissues of large yellow croaker,
In order to elucidate the significance and related mechanisms of microbial agents in modulating the growth of broilers, one-day-old Avian broilers were employed to investigate the effect of microbial agents on body weight, daily gain and feed efficiency at various stages. The birds in the experimental groups were given salmonella pullorum then fed with antibiotics to counteract it. The results showed that the average broiler weight of the oral microbial agent group at the age of 40 days was significantly increased by 16.58% from 1520 g to 1772 g (
In a completely randomized block design experiment, 16 ruminally cannulated male sheep with body weights of (40 ± 2.1) kg were fed twice daily (8:00 and 16:00) with concentrate and forage (50:50 on dry matter (DM) basis). Dietary treatments were supplemented with intraruminal doses of powdered
Protective effects of antioxidant additives of selenium and vitamin E on rats that consumed maize naturally contaminated with mycotoxins were explored in this paper. Thirty-two Wistar female rats were randomly divided into four groups. The control group was given the basic diet with normal maize. The contaminated maize group was given the diet in which normal maize was replaced by mycotoxin-contaminated maize. The selenium group and vitamin E group were respectively fed mycotoxin-contaminated diet supplemented with 0.4 mg?middot;kg-1 selenium from yeast or 100 mg?middot;kg-1 vitamin E. The trial lasted for 4 weeks. Compared with the control group, antioxidative status was decreased significantly in the contaminated maize group. However, the status in the selenium group and vitamin E group was increased significantly compared with the contaminated maize group. The activities of enzymes related with liver function were significantly higher in the contaminated maize group than those in the control group, whereas they were significantly lower in the selenium group and/or the vitamin E group compared to the contaminated maize group. It is concluded that selenium and vitamin E were able to alleviate oxidative stress and liver function damage due to the consumption of maize naturally contaminated with mycotoxins.
The objective of this research was to develop a detection method for
Porcine transmissible gastroenteritis virus (TGEV) is the causative agent of acute diarrhea of newborn piglets that provokes high mortality rates in affected farms. In this study, specific immunoglobulin from egg yolk against TGEV was produced by immunization of White leghorn hens. Enzyme-linked immunosorbent assay (ELISA) and virus neutralization (VN) test revealed that the specific antibody titer started to increase on the tenth day post-immunization, reached its peak on the eighth week, and remained at a high level until the last week that we tested. The prophylactic and therapeutic effects of egg yolk immunoglobulin (IgY) was investigated in piglets. IgY was found effective to increase piglets survival rate significantly after challenge exposures in prophylactic efficacy analysis. The therapeutic effects test revealed that the mortality was dramatically reduced by orally administered IgY. All these results in our study indicated that IgY specific to TGEV could be an alternative prophylactic method like colostral antibodies against TGEV in piglets.