Inheritance of resistance to zucchini yellow mosaic virus and watermelon mosaic virus in watermelon

High resistance to zucchini yellow mosaic virus-China strain (ZYMV-CH) and moderate resistance to watermelon mosaic virus (WMV) were found in a selection of PI 595203 (Citrullus lanatus var. lanatus), an Egusi type originally collected in Nigeria. Mixed inoculations showed primarily that these two viruses have no cross-protection. This fact may explain the high frequency of mixed infection often observed in commercial fields. When plants were inoculated with a mixture of the two viruses, the frequency of plants resistant to ZYMV was lower than expected, indicating that WMV infection may reduce the ability of a plant to resist ZYMV. We studied inheritance of resistance to ZYMV-CH and WMV, using crosses between a single-plant selection of PI 595203 and the ZYMV-susceptible watermelon inbreds 9811 and 98R. According to virus ratings of the susceptible parents, the resistant parent, and the F1, F2, and BC1 generations, resistance to ZYMV-CH was conferred by a single recessive gene, for which the symbol zym-CH is suggested. The high tolerance to WMV was controlled by at least two recessive genes.     

Inheritance of seed color in Capsicum

The mode of seed color inheritance in Capsicum was studied via an interspecific hybridization between C. pubescens Ruiz and Pav. (black seed color) and C. eximium Hunz. (yellow seed color). Black seed color was dominant over yellow seed color. The F(2) segregation pattern showed continuous variation. The generation means analysis indicated the presence of a significant effect of additive [d], dominance [h], and additive x additive [i] interaction for seed color inheritance. The estimate for a minimum number of effective factors (genes) involved in seed color inheritance was approximately 3.     

Inheritance of a dwarf seed stalk character in onion

Results are reported of crossing a dwarf seed stalk line (mean height 44.8 cm) from Israel with five inbred lines of the Rijnsburger type each having normal tall seed stalks (mean heights 83.1–105.9 cm). The seed stalk height of F₁ generations from these crosses was slightly greater than that of the Rijnsburger parents but segregation occurred in the F₂ giving plants which could be considered ‘dwarf’ and ‘normal’ with respect to seed stalk height. Selfing individual F₂‘dwarf’ plants produced F₃ progenies whose mean heights were in the dwarf range, and were significantly correlated with those of their F₂ parent. The results obtained in the F₂ and F₃ families suggest that although a major recessive gene for dwarfness may be present, substantial minor gene and environmental variation is also involved.     

Inheritance and mapping of seed lipoxygenase polypeptides in Pisum

Summary Analysis of crosses of Pisum lines showing variation in the apparent molecular weight of seed lipoxygenase polypeptides indicates that the genes encoding the two major pea seed lipoxygenase polypeptides are closely linked. The lipoxygenase locus, designated Lox, maps to a position on linkage group 4 between Np and le.     

Extraction of watermelon seed proteins with enhanced functional properties using ultrasound

Abstract

Watermelon seed is the potential source of value-added proteins, oils, and carbohydrates. The present study evaluates the extraction, and functional properties of watermelon seed protein (WMSP) obtained by ultrasound-assisted extraction (UAE) method from watermelon seed (WMS). The optimization of various operating parameters, such as pH (9), WMS powder to solvent ratio (1:50 w/v), temperature (30?±?2?°C), ultrasound power (90?W), frequency (25?kHz), and duty cycle (75%) has been carried out. The extraction yield obtained was 87% and the extraction time was lowered down to 9?min from 120?min of conventional batch extraction. It contains all essential amino acids in an adequate amount required for adults as per FAO/WHO guidelines while for 2–5?years old children, the content of valine and isoleucine are above the required range. Methionine and lysine contents are adequate for both children and adults. Functional properties of ultrasonic extracted proteins were found superior to conventionally extracted proteins.

• highlights

• The UAE method is more efficient for watermelon seed protein extraction.

• Impact of extraction parameters on the extraction yield was studied.

• Protein isolate with enhanced functional properties was obtained.

• Essential amino acid content was determined.

     

Inheritance of reduced linolenic acid content in soybean seed oil

 Linolenic acid is the unstable component of soybean [Glycine max (L.) Merr.] oil that is responsible for the undesirable odors and flavors commonly associated with poor oil quality. Two mutants, M-5 and KL-8, have been identified that have lower linolenic acid levels in the seed oil than the ‘Bay’ cultivar. Our objective was to determine the relationships between the genetic systems controlling linolenic acid in these mutants. Reciprocal crosses were made between the mutants and ‘Bay’, and between the two mutants. No maternal effect for linolenic acid content was observed from the analysis of F₁ seeds in any of the crosses. The data for linolenic acid content in F₂ seeds of M-5בBay’ and KL-8בBay’ crosses satisfactorily fit a 1 : 2 : 1 and 3 : 1 ratio, respectively. For the M-5×KL-8 cross, segregation observed from the analysis of F₂ seeds for linolenic acid content satisfactorily fit a ratio of 3 more than either mutant: 12 within the range of the two mutants: 1 less than either mutant. The segregation ratio of F₂ seeds and the segregation of F₃ seeds from F₂ plants indicated that M-5 and KL-8 have alleles at different loci that control linolenic acid content. The allele in KL-8 has been designated as fanx (KL-8) to distinguish it from fan (M-5). The low linolenic acid segregates with the genotype fanfanfanxfanx provide additional germplasm to reduce the linolenic acid content from the seed oil of soybean. Received: 18 December 1995 / Accepted: 12 July 1996     

Inheritance of seed dormancy in Tibetan semi-wild wheat accession Q1028

Tibetan semi-wild wheat (Triticum aestivum ssp. tibetanum Shao) is one of the Chinese endemic hexaploid wheat genetic resources, distributed only in the Qinghai-Xizang Plateau of China. It has special characters, such as a hulled glume and spike disarticulation. However, seed dormancy, another important character for wheat resistance to pre-harvest sprouting, was rarely reported. Seed dormancy of more than 10 Tibetan semi-wild wheat accessions was evaluated, and their germinations were 0% or near 0% with both treatments of threshed seeds and intact spikes at hard dough stage. Tibetan semi-wild wheat accession Q1028 was investigated for its seed dormant characters by testing the seed germination percentages of intact spikes, seeds with bract powder, normal seeds, seeds with pierced coat, and sectioned embryos. It was observed that embryo dormancy of Q1028 accounted for its seed dormancy. Using threshed seeds and intact spikes at hard dough stage, the inheritance of seed dormancy was carried out using the F1, F2, F3 and F2BC1 populations of the cross between Q1028 and a wheat line 88-1643, susceptible to preharvest sprouting. The germinations of seeds and intact spikes in F1 plants were 1.0% and 0.9%, respectively. It indicated that seed dormancy of Q1028 was inherited as a dominant trait. From the genetic analysis of the F2, F3 and F2BC1 populations it was found that the strong seed dormancy of Q1028 was controlled by two dominant genes.     

Inheritance of resistance to Phomopsis seed decay in PI 360841 soybean

Phomopsis longicolla Hobbs is the primary cause of Phomopsis seed decay (PSD) in soybean. Infection may result in moldy seed and poor germination. The objective of this study was to conduct inheritance studies to characterize resistance to PSD in plant introduction (PI) 360481. Crosses were made between PI 360841 and 2 PSD-susceptible genotypes, Agripro (AP) 350 and PI 91113, to determine the number of genes for resistance. Additionally, crosses were made between PI 360841 and Phomopsis resistant parents MO/PSD-0259 and PI 80837 to test the allelism of the resistance genes. Seed infection assays were done using seed from parent plants and F(2) populations. Chi-square analysis of the resistant x susceptible F(2) data fit to a 9R:7S model for 2 complementary dominant genes conferring PSD resistance in PI 360841. Segregation for reaction in the F(2) of MO/PSD-0259 x PI 360841 exhibited a good fit to a 57R:7S model for 2 complementary dominant genes from PI 360841 and a different dominant gene from MO/PSD-0259. There was no apparent segregation in the F(2) population from PI 360841 x PI 80837 except for one suspicious susceptible plant, suggesting one of the genes in PI 360841 is the same gene in PI 80837 for PSD resistance.     

Inheritance of seed yield and quality traits in peas (Pisum sativum L.)

Summary A half diallel analysis involving nine cultivars showed that additive as well as non-additive gene effects were important for the inheritance of seed yield per plant, 100-seed weights, protein content and potassium per cent. For remaining traits non-additive genetic components were important. Overdominance was observed for all traits except for 100-seed weight, which expressed partial dominance. Parents PMR-T10, EC21857, EC109182, T163 and EC109189 were good general combiners for seed yield, seed weight and quality traits. In general there was a good relationship between per se performance and the gca effects of the parents for all traits. Cross combinations such as LMR8 x EC109182,LMR8 x PMR-T10,LMR8 x EC21857,PMRT10 x EC21857 and P23 x EC21857 were found promising. The seed yield was positively correlated with other quality traits. Protein had a positive correlation with methionine and phosphorus. All the values of correlation co-efficients were non-significant except for yield with potassium, 100-seed weight and protein with methionine, indicating that yield and quality attributes can be improved simultaneously by simple selection procedures.     

Inheritance of high palmitic acid content in the seed oil of sunflower mutant CAS-5

 Sunflower genotypes with increased levels of palmitic acid (C16 : 0) in the seed oil could be useful for food and industrial applications. The objective of the present study was to determine the inheritance of the high C16 : 0 content in the sunflower mutant line CAS-5 (>25% of the total oil fatty acids). This mutant was reciprocally crossed with the lines HA-89 (5.7% C16 : 0) and BSD-2-691 (5.4% C16 : 0), the latter being the parental line from which CAS-5 was isolated. No maternal effect for the C16 : 0 content was observed from the analysis of F₁ seeds in any of the crosses. The inheritance study of the C16 : 0 content in F₁, F₂ and BC₁F₁ seeds from the crosses of CAS-5 with its parental line BSD-2-691 indicated that the segregation fitted a model of two alleles at one locus with partial dominance for the low content. The analysis of the fatty acid composition in the F₂ populations from the crosses with HA-89 revealed a segregation fitting a ratio 19 : 38 : 7 for low (<7.5%), middle (7.5–15%), and high (>25%) C16 : 0 content, respectively. This segregation was explained on the basis of three loci (P1, P2, P3) each having two alleles showing partial dominance for low content. The genotypes with a high C16 : 0 content were homozygous for the recessive allele p1 and for at least one of the other two recessive alleles, p2 or p3. This model was further confirmed with the analysis of the F₃ and the BC₁F₁ generations. It was concluded that both the recessive alleles p2 and p3 were already present in the BSD-2-691 line, the allele p1 being the result of a mutation from P1. This genetic study will facilitate breeding strategies associated with the incorporation of the high C16 : 0 trait into agronomically acceptable sunflower hybrids. Received: 30 March 1998 / Accepted: 13 August 1998     

Inheritance of high oleic acid content in the seed oil of soybean mutant M23

A mutant line, M23, of soybean [Glycine max (L.) Merr.] was found to have two fold increases in oleic acid content in the seed oil compared with the original variety, Bay. Our objective was to determine the inheritance of the high oleic acid content in this mutant. Reciprocal crosses were made between M23 and Bay. There were no maternal and cytoplasmic effects for oleic acid content. The F₁ seeds and F₁ plants were significantly different from either parents or the midparent value, indicating partial dominance of oleic acid content in these crosses. The oleic acid content segregated in the F₂ seeds and F₂ plants in a trimodal pattern with normal, intermediate and high classes, satisfactorily fitting a 121 ratio. The seeds of a backcross between M23 and F₁ segregated into intermediate and high classes in a ratio of 11. These results indicated that oleic acid content was controlled by two alleles at a single locus with a partial dominant effect. Thus, the allele in M23 was designated ol and the genotypes of M23 and Bay were determined to be olol and 0l0l, respectively. The oleic acid contents of the F₂ seeds and F₂ plants were inversely related with the linoleic acid content which segregated in a trimodal pattern with normal, intermediate and low classes in a 121 ratio. Thus, it was assumed that the low linoleic acid content in M23 was also controlled by the ol alleles. Because a diet with high oleic acid content reduces the content of low density lipoprotein cholesterol in blood plasma, the mutant allele, ol, would be useful in improving soybean cultivars for high oleic acid content.     

Biochemical changes in fermented melon (egusi) seeds (Citrullis vulgaris)

Summary Biochemical and sensory changes of Nigerian melon seeds fermented with fourBacillus strains isolated from African locust beans were studied. In all fermentations, the reducing sugar content doubled from a starting value of 45 mg/g. The total free amino acid content decreased for the first 40 h and then increased. WithB. licheniformis, B. subtilis andB. pumilis, there was a subsequent large increase in free amino acid content. The extracted oils in the fermentation product increased in saponification number and free acid content but decreased in iodine number. The sensory properties of theB. licheniformis product was similar to that of ogiri and that ofB. subtiis to Iru.     

Inheritance of seed iron and zinc concentrations in common bean (Phaseolus vulgaris L.)

Micronutrients are essential elements needed in small amounts for adequate human nutrition and include the elements iron and zinc. Both of these minerals are essential to human well-being and an adequate supply of iron and zinc help to prevent iron deficiency anemia and zinc deficiency, two prevalent health concerns of the developing world. The objective of this study was to determine the inheritance of seed iron and zinc accumulation in a recombinant inbred line (RIL) population of common beans from a cross of low × high mineral genotypes (DOR364 × G19833) using a quantitative trait locus (QTL) mapping approach. The population was grown over two trial sites and two analytical methods (Inductively Coupled Plasma Spectrometry and Atomic Absorption Spectroscopy) were used to determine iron and zinc concentration in the seed harvested from these trials. The variability in seed mineral concentration among the lines was larger for iron (40.0–84.6 ppm) than for zinc (17.7–42.4 ppm) with significant correlations between trials, between methods and between minerals (up to r = 0.715). A total of 26 QTL were identified for the mineral × trial × method combinations of which half were for iron concentration and half for zinc concentration. Many of the QTL (11) for both iron (5) and zinc (6) clustered on the upper half of linkage group B11, explaining up to 47.9% of phenotypic variance, suggesting an important locus useful for marker assisted selection. Other QTL were identified on linkage groups B3, B6, B7, and B9 for zinc and B4, B6, B7, and B8 for iron. The relevance of these results for breeding common beans is discussed especially in light of crop improvement for micronutrient concentration as part of a biofortification program.     

Inheritance of seed desiccation sensitivity in a coffee interspecific cross: evidence for polygenic determinism

The genetic determinism of seed desiccation sensitivity was studied using a cross between two coffee species exhibiting a large difference for this trait, Coffea pseudozanguebariae (tolerant) and C. liberica (sensitive). Throughout the whole study, seed desiccation tolerance was quantified both in terms of water content and water activity. Whatever the parameter used, the level of seed desiccation tolerance in F1 hybrids corresponded to that of the mid-parent, thus indicating an additive inheritance of seed desiccation tolerance at the F1 level. A broad variation was observed among hybrids backcrossed to C. liberica (BCs) for seed desiccation tolerance, independent of the parameter used to quantify it. This variation was continuous and BCs showed transgression in the direction of the most desiccation sensitive parent, indicating (i) that desiccation tolerance is a polygenic trait in coffee species, and (ii) that C. pseudozanguebariae does not present the most favourable alleles for all the genes involved in seed desiccation tolerance. No significant difference was observed between the two reciprocal backcrosses, F1xC. liberica and C. libericaxF1, for the level of desiccation tolerance of their seeds, showing the absence of a maternal effect on this trait. There was no significant effect of the number of seeds harvested from each BC on the level of desiccation tolerance of its seeds. Moreover, there was no significant correlation within BCs between seed size, seed viability, and water content before desiccation and desiccation tolerance.     

Inheritance of low linolenic acid content of the seed oil of a mutant in Glycine max

Summary Linolenic acid content of the oil from F₁, F₂, and F₃ seeds was compared with the parental values from a cross between a soybean cultivar with high (7.0%) and a mutant line with low (3.4%) linolenate (183). Linolenic acid content of F₁ seeds was intermediate to that of selfed seeds from the two parents and values from reciprocal crosses were essentially the same. This demonstrated that in this cross, linolenic acid content of the oil was controlled by the embryo rather than by the maternal parent. The distribution of linolenic acid in F₂ seeds from F₁ plants was trimodal and extended across the range of parental values. High and low linolenate F₂ plants bred true for 183 content and the F₃ distribution of seeds from F₂ plants with intermediate levels of 183 was similar to the F₂ distribution. The data were consistent with a model for two alleles with additive effects at a single locus controlling percent linolenic acid in these progenies. The simply-inherited alleles for low linolenate could be readily transferred to agronomically superior soybean cultivars, which would improve the fatty acid composition of the oil.Cooperative Investigations of the Northern Regional Research Center, ARS, USDA, Peoria, Illinois and the Purdue Univ. Agric. Exp. Stn. Journal Paper No. 10,020 of the Purdue Univ. Agric. Exp. Stn.     

Soil moisture level and substrate type determine long-term seed lifespan in a soil seed bank

Plant and Soil - Seeds are usually classified as short- or long-term persistent. It is still hardly understood how environmental conditions influence seed persistence. The study aimed to monitor...     

Inheritance of seed colour and identification of RAPD and AFLP markers linked to the seed colour gene in rapeseed (Brassica napus L.)

In China Polima cytoplasmic male sterility (cms) is currently the most important hybrid system used for the breeding of hybrids. In an effort to develop yellow-seeded Polima cms restorer lines, we used yellow-seeded, doubled haploid (DH) line No.2127-17 as the gene source in crosses with two elite black-seeded Polima cms R lines, Hui5148-2 and 99Yu42, which originated from our breeding programme. The inheritance of seed colour was investigated in the F₂, BC₁ and F₁-derived DH progenies of the two crosses. Seed colour was found to be under the control of the maternal genotype and the yellow seed trait to be partially dominant over the black seed trait. Segregation analysis revealed a single gene locus for the partial dominance of yellow seed colour. Of 810 randomly amplified polymorphic DNA (RAPD) primers, 240 (29.6%) revealed polymorphisms between the parents. Of the 240 RAPD primers and 512 amplified fragment length polymorphism (AFLP) primer pairs, four RAPDs and 16 AFLP pairs showed polymorphisms between the bulks, with two RAPD and eight AFLP markers being identified in the vicinity of the seed-coat colour gene locus using a DH progeny population—derived from the cross Hui5148-2×No.2127-17—of 127 individuals in combination with the bulked segregant analysis strategy. Seven of these latter ten markers were linked to the allele for yellow seed, whereas the other three were linked to the allele for black seed. The seed-coat colour gene locus was bracketed by two tightly linked markers, EA02MG08 (2.4 cM) and S1129 (3.9 cM). The partial dominance and single gene control of the yellow seed-coat colour trait together with the available molecular markers will greatly facilitate the future breeding of yellow-seeded hybrid varieties.     

Inheritance of seed protein content and other agronomic characters in long bean (Vigna sesquipedalis Fruw.)

Summary Seven varieties of long bean, which included three local and four exotic, were crossed in a complete diallel. This was an attempt to study the inheritance of crude protein content, protein yield, flowering date, pod yield and yield components.Both additive and non-additive gene effects were responsible for the genetic variation in the diallel population. However, dominance variance was more important than additive variance in crude protein content, number of pods per plant and number of seeds per pod. For seed weight and pod length, additive variance was more important.The crude protein content, protein yield and number of pods per plant appeared to be controlled by overdominance effects. Partial dominance seemed to be the case for flowering date, pod length and seed weight; complete to overdominance for pod yield. High protein appeared to be associated with recessive genes whereas there was a general trend of high yielding parents carrying more dominant genes.     

Effects of disperser abundance, seed type, and interspecific seed availability on dispersal distance

Seed dispersal distance is influenced by a variety of seed properties and functional responses of dispersers. However, to our knowledge, how and why seed dispersal distances are determined remains poorly understood. In the present study, seeds of sympatric tree species, Pinus koraiensis, Corylus mandshurica, Corylus heterophylla, and Quercus mongolica were released to investigate the effects of rodent abundance, seed type, and seed availability on seed dispersal. Our results showed that seeds of P. koraiensis were dispersed further than those of C. heterophylla and C. mandshurica regardless of the ambient rodent and seed abundances, reflecting a consistent effect of seed type on seed dispersal distances. Seed dispersal distance was greatly facilitated by lower per-capita seed abundance (the ratio of seeds to rodents); however, seed caching and cache survival were benefited from higher per-capita seed abundance. Although seed dispersal and seed caching of a particular tree species can be enhanced by its own seed availability, no consistent influence was detected at interspecific levels, reflecting different interspecific effects of seed availability on seed dispersal of sympatric seed species. Our results provide evidences that the effect of seed availability on seed dispersal should be evaluated in terms of per-capita seed abundance and interspecific effects, rather than the independent influence of seed or disperser abundances.     

Cytokinins in immature seeds of watermelon

Immature seeds of watermelon contain at least three cytokinins which are extracted by methanol, adsorbed on cation-exchange resin, and can be eluted with ammonia. One of the factors (Factor III) has a Rf value close to that of zeatin, 6-(γ,γ-dimethylallylamino)-purine and triacanthine when chromatographed in different solvent systems but represents only a small fraction of the total cytokinin activity of the seeds. The major part of the activity is due to two other factors. Factor II exhibits Rf values different from the cytokinins reported in literature and appears to be new.