水稻RFLP连锁图谱的构建及控制小穗不育和花粉不育的QTL分析

用台中65(粳稻)/ARC10313(籼稻)的重组近交系(F10)构建了RFLP连锁图谱, 含113个分布均匀的标记. 作成的图谱覆盖全基因组, 全图总长1462.4 cM, 图中标记位置与所使用的参照图谱基本符合. 利用该重组自交家系材料与亲本台中65回交得到BF1家系, 用于对小穗不育和花粉不育的QTL分析, 检测出3个小穗不育和1个花粉不育QTL, 且有一     

Pythium rot of figmarigold (<Emphasis Type="Italic">Lampranthus spectabile</Emphasis>) caused by <Emphasis Type="Italic">Pythium aphanidermatum</Emphasis>

A new leaf rot disease was found on the leaves of figmarigold (Lampranthus spectabile). The causal organism, identified as Pythium aphanidermatum was found to cause the same symptoms after artificial inoculation and was then reisolated from the inoculated plants. We propose to name the disease Pythium rot of figmarigold.     

Waxy endosperm accompanies increased fat and saccharide contents in bread wheat (Triticum aestivum L.) grain

The contents of fat, starch, pentosan, fructan, β-glucan and several mono- and oligosaccharides in grain were evaluated to find out the possible effects of the Wx-D1 gene of bread wheat using two sets of near-isogenic waxy and non-waxy lines and two low-amylose mutant lines with a common genetic background of Kanto 107. These materials have two non-functional Wx-A1b and Wx-B1b alleles in common. Waxy near-isogenic lines with a non-functional Wx-D1d allele showed consistently increased contents of fat, total fructan, β-glucan, glucose, fructose, sucrose, 1-kestose, 6-kestose, neokestose, nystose and bifurcose compared with non-waxy lines with a functional Wx-D1a allele throughout three growing/harvest seasons. Starch and total pentosan contents were inconsistently influenced by the allelic status of the Wx-D1 locus, while water-soluble pentosan and raffinose contents were not affected. The compositional changes of a low-amylose mutant line with an almost non-functional Wx-D1f allele were closely similar to those of waxy near-isogenic lines, while significantly different changes were barely observed in another low-amylose mutant line with a partly functional Wx-D1g allele in two seasons. These results showed that the Wx-D1 gene has pleiotropic effects on the fat and saccharide contents of bread wheat grain.     

Rapid genotyping with DNA micro-arrays for high-density linkage mapping and QTL mapping in common buckwheat (Fagopyrum esculentum Moench)

For genetic studies and genomics-assisted breeding, particularly of minor crops, a genotyping system that does not require a priori genomic information is preferable. Here, we demonstrated the potential of a novel array-based genotyping system for the rapid construction of high-density linkage map and quantitative trait loci (QTL) mapping. By using the system, we successfully constructed an accurate, high-density linkage map for common buckwheat (Fagopyrum esculentum Moench); the map was composed of 756 loci and included 8,884 markers. The number of linkage groups converged to eight, which is the basic number of chromosomes in common buckwheat. The sizes of the linkage groups of the P1 and P2 maps were 773.8 and 800.4 cM, respectively. The average interval between adjacent loci was 2.13 cM. The linkage map constructed here will be useful for the analysis of other common buckwheat populations. We also performed QTL mapping for main stem length and detected four QTL. It took 37 days to process 178 samples from DNA extraction to genotyping, indicating the system enables genotyping of genome-wide markers for a few hundred buckwheat plants before the plants mature. The novel system will be useful for genomics-assisted breeding in minor crops without a priori genomic information.     

Angiotensin I Converting Enzyme Inhibitory Peptides Derived from Phycobiliproteins of Dulse Palmaria palmata

We examined the inhibitory activity of angiotensin I converting enzyme (ACE) in protein hydrolysates from dulse, Palmaria palmata. The proteins extracted from dulse were mainly composed of phycoerythrin (PE) followed by phycocyanin (PC) and allophycocyanin (APC). The dulse proteins showed slight ACE inhibitory activity, whereas the inhibitory activity was extremely enhanced by thermolysin hydrolysis. The ACE inhibitory activity of hydrolysates was hardly affected by additional pepsin, trypsin and chymotrypsin treatments. Nine ACE inhibitory peptides (YRD, AGGEY, VYRT, VDHY, IKGHY, LKNPG, LDY, LRY, FEQDWAS) were isolated from the hydrolysates by reversed-phase high-performance liquid chromatography (HPLC), and it was demonstrated that the synthetic peptide LRY (IC₅₀: 0.044 μmol) has remarkably high ACE inhibitory activity. Then, we investigated the structural properties of dulse phycobiliproteins to discuss the origin of dulse ACE inhibitory peptides. Each dulse phycobiliprotein possesses α-subunit (Mw: 17,477–17,638) and β-subunit (Mw: 17,455–18,407). The sequences of YRD, AGGEY, VYRT, VDHY, LKNPG and LDY were detected in the primary structure of PE α-subunit, and the LDY also exists in the APC α- and β-subunits. In addition, the LRY sequence was found in the β-subunits of PE, PC and APC. From these results, it was suggested that the dulse ACE inhibitory peptides were derived from phycobiliproteins, especially PE. To make sure the deduction, we carried out additional experiment by using recombinant PE. We expressed the recombinant α- and β-subunits of PE (rPEα and rPEβ, respectively), and then prepared their peptides by thermolysin hydrolysis. As a result, these peptides showed high ACE inhibitory activities (rPEα: 94.4%; rPEβ: 87.0%). Therefore, we concluded that the original proteins of dulse ACE inhibitory peptides were phycobiliproteins.     

Ultracytochemical demonstration of glycoproteins in the eccrine glands of the digital pads of the North American raccoon (Procyon lotor)

In the eccrine glands of the digital pads of the North American raccoon (Procyon lotor), ultrastructural localization of glycoproteins with various saccharide residues was studied using preferably lectin cytochemical methods. Secretory granules observed in the dark cells exhibited glycoproteins with different terminal sugars (alpha-D-mannose, beta-D-galactose, beta-N-acetyl-D-glucosamine and sialic acid). The cytoplasm of the clear cells contained numerous glycogen particles. Several sugars were also detectable in the surface coat of the plasma membrane of the secretory cells. The results obtained could be helpful in understanding secretion production and cell related secretion functions of the eccrine glands of the raccoon digital foot pads.     

Effect of chinese parsley Coriandrum sativum and chitosan on inhibiting the accumulation of cadmium in cultured rainbow trout Oncorhynchus mykiss

ABSTRACT:   Toxic heavy metals such as cadmium (Cd) accumulate in cultured fish from solid-form feed mixtures. In this paper, two natural ingredients, supposed to inhibit accumulation of heavy metals in the fish body, were investigated to develop a functional feed mixture for healthy fish. Three test diets: (i) ♯1, regular diet as negative control; (ii) ♯2, ♯1 + 2% lyophilized Chinese parsley Coriandrum sativum (CP); and (iii) ♯3, ♯1 + 3% chitosan (CT), were each fed to 50 rainbow trout Oncorhynchus mykiss once a day, at the constant rate of 1.0–1.2% of body weight for 12 weeks. No undesirable effect on fish growth was observed by an addition of either CP or CT to regular feed. Then, 10 mg Cd was added to 1 kg each of the three test diets and they were named as: (i) ♯4, ♯1 + Cd; (ii) ♯5, ♯2 + Cd; and (iii) ♯6, ♯3 + Cd, respectively. The fish given positive a control feed (diet ♯4) for 3 weeks accumulated Cd in the liver and kidney at approximately 0.52 mg/kg. However, Cd in ordinary muscle was found to be just above the detection limit. Upon accumulation of Cd, three groups of 50 fish were each fed test diets ♯4, ♯5, and ♯6 for 12 weeks at the same feed rate described above. The concentrations of Cd accumulated in the liver, kidney, and ordinary muscle of the fish were measured every 3 weeks. Contrary to the positive control fish fed diet ♯4, those fish fed test diets ♯5 and ♯6 accumulated 20–30% and 25–40% less Cd in the liver, respectively. Test diets were a little less effective for inhibition of Cd uptake in the kidney than that observed in the liver. These results suggest that addition of CP or CT to fish feed might be used to decrease toxic heavy metal accumulation in fish.     

Mechanism of acid-neutralization in two Japanese watersheds

In Japan, acidification of terrestrial water has not yet been reported except lakes acidified by volcano or mine. However, acid deposition in Japan is as much as those in northern Europe and north-eastern U.S.A., and acidification of terrestrial water may occur in future. In order to predict long-term acidification, it is necessary to understand acid-neutralization mechanism in watershed. Therefore, two experimental watersheds study for geology, hydrology, and water chemistry were conducted. On the basis of these data, chemical change in percolation of precipitation through watersheds and acid-neutralization mechanism are analyzed. The principal results are: (1) Acid deposition is neutralized continuously in percolation of precipitation from ground-surface to aquifer, (2) Chemical weathering of primary minerals plays an important role in the acidneutralization in the watersheds, and should be quantified and taken into account in the long-term prediction of acidification.     

Application of inorganic element ratios to chemometrics for determination of the geographic origin of welsh onions

The composition of concentration ratios of 19 inorganic elements to Mg (hereinafter referred to as 19-element/Mg composition) was applied to chemometric techniques to determine the geographic origin (Japan or China) of Welsh onions (Allium fistulosum L.). Using a composition of element ratios has the advantage of simplified sample preparation, and it was possible to determine the geographic origin of a Welsh onion within 2 days. The classical technique based on 20 element concentrations was also used along with the new simpler one based on 19 elements/Mg in order to validate the new technique. Twenty elements, Na, P, K, Ca, Mg, Mn, Fe, Cu, Zn, Sr, Ba, Co, Ni, Rb, Mo, Cd, Cs, La, Ce, and Tl, in 244 Welsh onion samples were analyzed by flame atomic absorption spectroscopy, inductively coupled plasma atomic emission spectrometry, and inductively coupled plasma mass spectrometry. Linear discriminant analysis (LDA) on 20-element concentrations and 19-element/Mg composition was applied to these analytical data, and soft independent modeling of class analogy (SIMCA) on 19-element/Mg composition was applied to these analytical data. The results showed that techniques based on 19-element/Mg composition were effective. LDA, based on 19-element/Mg composition for classification of samples from Japan and from Shandong, Shanghai, and Fujian in China, classified 101 samples used for modeling 97% correctly and predicted another 119 samples excluding 24 nonauthentic samples 93% correctly. In discriminations by 10 times of SIMCA based on 19-element/Mg composition modeled using 101 samples, 220 samples from known production areas including samples used for modeling and excluding 24 nonauthentic samples were predicted 92% correctly.