New Leaf Spot Disease of Cymbidium Species Caused by Fusarium subglutinans and Fusarium proliferatum

Fusarium species were consistently isolated from yellow, swollen spots with reddishbrown centers and small black spots on leaves of Cymbidium plants in the greenhouse. Fusarium subglutinans caused the yellow spots and Fusarium proliferatum caused either the yellow or the black spots. We propose the name “yellow spot” for the new disease. To denote differences in their pathogenicity to orchid plants, we designate the population causing yellow spot as race Y and that causing black spot as race B of F. proliferatum. Received 29 October 1999/ Accepted in revised form 10 March 2000     

Evaluation of colorimetric pH strips for wild animal meat using image analysis

Colorimetric pH strips (MColorpHast™) are very convenient to use, but the decision of pH is based on an individual's color perception and is, therefore, subjective. We developed a pH calculation program for the image of coloring strips on CIE1976 (L*a*b* color space), which slightly underestimated human judgment as the color of pH darker. This image analysis and three individuals' judgments were used for evaluating the strip's features for various qualities of meat from wild animals, and the results were compared with the assessments based on potentiometric pH. In both methods, dipping the strips in distilled water just before use improved the regression coefficient compared with that mentioned in the manual. The image analysis showed higher correlation than human judgments but slightly underestimate pH by a maximum of 0.13 unit from the regression line of the potentiometric pH. In addition, the image analysis revealed meat pigment changed pH higher on the color scale in the lower meat pH region. The strips must be used according to the manual, but dipping is effective when the meat surface is dry, and keeping the strips from touching the meat drip is important in lower pH region because the pigment affects the color of pH.     

Quercetin-dependent reduction of salivary nitrite to nitric oxide under acidic conditions and interaction between quercetin and ascorbic acid during the reduction

A salivary component, nitrate, is reduced to nitrite in the oral cavity. Polyphenols in foods are mixed with nitrite in the saliva to be swallowed into the stomach. An objective of the present study is to elucidate reactions between a polyphenol quercetin and a nitrite under acidic conditions. Nitric oxide, which is formed by the reactions between nitrous acid and quercetin or ascorbic acid (AA), can be measured using an oxygen electrode in the saliva as well as a buffer solution. The initial oxidation of quercetin was inhibited by AA, and quercetin enhanced the oxidation of AA, suggesting AA-dependent reduction of quercetin radicals, which might be formed during the oxidation of quercetin by nitrous acid. On the basis of the above results, the usefulness of an oxygen electrode for the measurement of nitrite-dependent nitric oxide formation under acidic conditions is proposed and the possible mechanism of reduction of nitrous acid by quercetin and the interaction between quercetin and AA, which is a normal component in the gastric juice, for the reduction of nitrous acid is discussed.     

Effect of spore inoculum and agricultural practices on the vertical distribution of the biocontrol plant-growth-promoting bacterium <Emphasis Type="Italic">Pasteuria penetrans</Emphasis> and growth of <Emphasis Type="Italic">Meloidogyne incognita</Emphasis>-infected tomato

Three concentrations of Pasteuria spores applied to soil and some agricultural practices were evaluated for their effects on spore attachment to nematodes and biocontrol of Meloidogyne incognita on tomato in a microplot experiment. Applications of Pasteuria at concentrations of 5᎒¹⁰ spores/m² increased tomato fruit yield per plant by 46% compared to non-Pasteuria treatments but also increased nematode densities in soil at harvest time. M. incognita juveniles recovered from plots where Pasteuria was applied at 5᎒¹⁰ spores/m² showed greater spore attachment than those with application rates of 2.5᎒⁹ spores/m² or 5᎒⁹ spores/m². Pasteuria spores penetrated to 30-40 cm soil depth in a volcanic ash sandy soil after application of spore suspensions to the soil surface. Densities of over 2.5᎒⁴ spores/g of soil were reached at 0-30 cm soil depth only when the application rate was 5᎒¹⁰ spores/m², but at harvest and after fallow densities of about 2.5᎒⁴ spores/g of soil were also reached in the top 10 cm of soil at 2.5᎒⁹ and 5᎒⁹ spores/m² application rates. Spore densities in soil decreased after 6 months of fallow when densities at harvest time were higher than 10⁵ spores/g of soil. Tillage and additional watering 2 days after spore application increased spore densities in soil at harvest throughout the soil depth (0-40 cm).     

Interspecific hybrids betweenAllium fistulosumandAllium schoenoprasumreveal carotene-rich phenotype

Interspecific hybridization is an effective method to generate a new crop that gains available functions in a short time. Interspecific hybrids (2n= 16) betweenAllium fistulosumL. (2n= 16) andAllium schoenoprasumL. (2n= 16) were produced by reciprocal crossings through ovary culture, but the hybrids were much fewer in the combination usingA. schoenoprasumas a seed plant. All the hybrids have eight long chromosomes originated fromA.fistulosumand eight short chromosomes originated fromA. schoenoprasum. In addition, the hybridity was confirmed by randomly amplified polymorphic DNA (RAPD) analysis and cleaved amplified polymorphic sequence (CAPS) analysis of the rDNA internal transcribed spacer (ITS) region. The interspecific hybrids showed a vigorous growth habit; their foliage was slightly bloomy and deep green. The hybrids did not form bulbs, but rather propagated vegetatively by tillering. Carotene contents of the hybrids and both parents were quantified using high-performance liquid chromatography (HPLC). The contents of all edible parts of the hybrids were approximately seven times higher than those of either parent. These results indicate that the hybrid is a new and carotene-rich vegetable ofAlliumspecies.     

Production of interspecific hybrids between Alstroemeria pelegrina L. var. rosea and A. magenta Bayer by ovule culture

Interspecific hybrids were efficiently produced in the cross-incompatible combination between Alstroemeria pelegrina L. var. rosea and A. magenta Bayer by culturing immature ovules with placenta 7–14 days after pollination on 2 g/l Gelrite-solidified MS medium containing 3% (w/v)sucrose. The plants showed intermediate characteristics between the parents and their hybridity was confirmed by karyotype and DNA analyses. The mean number of chromosome association per PMC at metaphase I was 2.60I+6.70II, pollen stainability was20.8%, and they produced viable seeds after self-pollination. Furthermore, mature plants were obtained when the hybrids were backcrossed as male parents with both the parents. The backcross-progeny from A. pelegrina var. rosea × hybrids exhibited 3.8 to 79.7% pollen stainability and that from A. magenta × hybrids 78.8 to 98.3%. Almost all of these plants produced viable seeds after self-pollination, which implies that they can beutilized for breeding of novel cultivars of Alstroemeria. This revised version was published online in July 2006 with corrections to the Cover Date.     

Insemination of recipient sows improves the survival to term of vitrified and warmed porcine expanded blastocysts transferred non‐surgically

This study was performed to evaluate reproductive performance after non‐surgical embryo transfer (Ns‐ET) of 10–15 porcine expanded blastocysts (ExBs) that had been vitrified and warmed (V/W) using the micro volume air cooling (MVAC) method. The effect of asynchrony between the donor and recipient estrous cycle was investigated. Ns‐ET was conducted in recipients whose estrous cycle was asynchronous to that of donors by a delay of 2, 1, or 0 days. In the 2‐day and 1‐day groups, the similar farrowing rates (27.3% and 25.0%) and survival rates to term (13.9% and 15.7%) were obtained after Ns‐ET of V/W ExBs. None of the recipients in 0‐day group farrowed. Artificial insemination (AI) prior to Ns‐ET was then evaluated. Ten–15 V/W ExBs were transferred non‐surgically to 12 recipients whose estrous cycles were asynchronous to that of donors by a 2‐day delay. All of the recipients produced piglets, and all (100.0%) delivered piglets were derived from the transferred V/W ExBs. The survival rate of V/W ExBs to term was 25.2%. These results demonstrate that Ns‐ET of V/W ExBs using MVAC can facilitate piglet production, even if 10–15 embryos are transferred. Moreover, piglets were obtained stably when AI was performed prior to Ns‐ET.