Seed dispersal of Acacia erioloba by African bush elephants in Hwange National Park, Zimbabwe

Approximately two-thirds (64%) of all dry season samples of elephant dung analysed during a 3-year study in the Main Camp subregion of Hwange National Park, Zimbabwe, contained seed and/or pod materials from Acacia erioloba . Most seeds were recovered intact and actively germinating seeds were not uncommon. Very little pod mass relative to seed mass was recovered in most instances, with pod fragments recorded from only 56% of all exhaustively sampled elephant dung piles containing A. erioloba fruit materials. Nonetheless, large pod fragments and even entire intact pods were recovered occasionally from elephant dung. Seeds and pods of A. erioloba may comprise 12% or more of total wet-weight dung mass; individual dung piles were found which contained > 5000 A. erioloba seeds. Birds and smaller mammals search out and consume A. erioloba seeds present within elephant dung piles. The findings of this study indicate that potential digestibility of A. erioloba seeds for bush elephants ( Loxodonta africana africana ) may be much higher than expected from previous studies. In controlled feeding trials with captive bush elephants (age 11–15 years old) maintained on predominantly free-range dry season diets, the estimated efficiency of digestion for A. erioloba seeds consumed in pods was 81% to 96%, with a gut-transit time of between 24.5 and 36.0 h. On the basis of throughput times determined in experimental feeding trials, potential elephant-dispersal distances of 20–50 km are predicted for A. erioloba in the Kalahari Sands landscapes of southern central Africa.     

SEED SIZE AND SEED PACKAGING VARIATION IN BAPTISIA LANCEOLATA (FABACEAE)

Pods and seeds of field-collected Baptisia lanceolala plants were analyzed to partition seed weight and seed packaging trait variance among and within plants and to detect relationships between these traits. Packaging traits studied were: pod weight, seed weight per pod, number of seeds per pod, mean weight of seeds per pod, proportion seed weight of total pod weight, and pod weight per seed. Significant among-plant variation was found for seed weight and all packaging traits. Within plants, positive correlations were found between number of seeds per pod and pod dry weight and between the proportion seed weight of total pod weight and number of seeds per pod. Pod weight per seed was negatively correlated with number of seeds per pod. Most plants had a negative correlation between mean seed weight and number of seeds per pod. When compared with an equality of slopes test, slopes of regressions of the above pairs of traits were found to differ among plants. Among plants, the same relationships were found, except for the latter two traits, which were not correlated. These within-plant patterns may represent constraints on seed weight variance imposed by the seed package. This view is supported by a positive correlation between packaging trait variance and seed weight variance. Packaging-related constraints could have an effect on seed weight in this and other species. If these phenotypic constraints have a genetic basis, then selection on seed packaging could change seed weight in a way different from that which might be predicted by considering seed weight alone.     

Quantitative trait locus analysis of multiple agronomic traits in the model legume Lotus japonicus.

The first quantitative trait locus (QTL) analysis of multiple agronomic traits in the model legume Lotus japonicus was performed with a population of recombinant inbred lines derived from Miyakojima MG-20 x Gifu B-129. Thirteen agronomic traits were evaluated in 2004 and 2005: traits of vegetative parts (plant height, stem thickness, leaf length, leaf width, plant regrowth, plant shape, and stem color), flowering traits (flowering time and degree), and pod and seed traits (pod length, pod width, seeds per pod, and seed mass). A total of 40 QTLs were detected that explained 5%-69% of total variation. The QTL that explained the most variation was that for stem color, which was detected in the same region of chromosome 2 in both years. Some QTLs were colocated, especially those for pod and seed traits. Seed mass QTLs were located at 5 locations that mapped to the corresponding genomic positions of equivalent QTLs in soybean, pea, chickpea, and mung bean. This study provides fundamental information for breeding of agronomically important legume crops.     

Soybean pod set enhancement with synthetic cytokinin analogs

The previously reported activity of benzyladenine and selected other cytokinin analogs to increase pod set in soybean (Glycine max [L.] Merr.) was further investigated to define the structure-activity relationship and evaluate the effects of the cytokinins on yield parameters. Enhancement of pod set was found to be greatest with N-6 saturated alkyl substituted analogs, and was only weakly associated with activity in a callus growth bioassay. The response of yield parameters to increasing pod load was evaluated by applying various cytokinin analogs having a range of pod set enhancement activity. The increased pod load at the treated nodes was not compensated by a reduction in pod number on the remainder of the plant. However, there was a compensatory decrease in seed size. Overall, a significant trend to greater total seed weight per plant was associated with the increased pod number. Initial evaluations indicated that foliar applications of select cytokinins could temporarily increase pod number. However, the increases in pod number obtained with foliar treatments were too small to be of practical utility and were not maintained to maturity.     

Changes in free polyamines and related enzymes during stipule and pod wall development in Pisum sativum

Level of free polyamines, their key metabolic enzymes, and other features related to ageing were examined during stipule and pod wall development in pea (Pisum sativum). Free polyamine titre (per unit fresh mass) in both the organs, the specific activities of arginine decarboxylase and ornithine decarboxylase in the pod wall, gradually decreased with maturation. In stipule, these enzymes attained peak activity at 15 days after pod emergence and declined thereafter. Ornithine decarboxylase activity was greater in pod wall than in stipule; while, arginine decarboxylase activity was higher in stipule. Activity of degradative enzyme diamine oxidase increased with the onset of senescence in both the organs. Chlorophyll and electrical conductance had a inverse relationship throughout the experimental period, whereas, the chlorophyll content was directly related with polyamine levels in both stipule and pod wall during aging. On the other hand, protein and RNA contents were positively correlated with free polyamines throughout the test period in stipule, but in the pod wall this was true only for the later stages of development.     

Pod Formation and Its Geotropic Orientation in the Peanut, Arachis hypogaea L., in Relation to Light and Mechanical Stimulus

Gynophore elongation, pod formation and pod orientation in thepeanut plant (Arachis hypogaea L.) were studied in relationto the effects of light and dark conditions, mechanical stimulus,and growth substances. It was found that the proembryos controlgynophore elongation, probably by secretion of growth regulatorswhich stimulate cell division in the intercalary meristem locatedproximal to the ovules. The stimulus of pod production causesthe development of the proembryo into a mature embryo simultaneouslywith the growth of pod tissues and the cessation of gynophoreelongation. Darkness was found to be an essential factor forthe induction of pod formation. Pod formation did not occurin any of the treatments performed in the light, including theapplication of different growth substances on the ovary. A mechanicalstimulus is needed, in addition to darkness, for the normalthickening and diageotropic orientation of the pod, caused bya higher growth rate of the basal proximal side of the pod.The two ovules are always located on the upper wall of the diageotropicallyoriented pod (ventral suture). A possible mechanism which causessuch an orientation is discussed.     

GC/MS and LC/MS Phytochemical Analysis of Vigna unguiculata L. Walp Pod

Vigna unguiculata (L. Walp) or Cowpea pod methanolic extracts phytochemical analysis, total phenolic content (TPC), and secondary metabolite profiling were determined using gas chromatography-mass spectrometry (GC/MS) and liquid chromatography-mass spectrometry (LC/MS) analysis. GC/MS analysis revealed twenty compounds in the extract, while LC/MS analysis identified twenty-four compounds. GC/MS chromatogram analysis suggested the presence of opioid α-N-Normethadol a major constituent found in methanolic extract and fatty acid esters carotenoid is found second major constituent. LC/MS chromatogram and the mass spectral analysis demonstrated the presence of flavonoids, carotenoids, and alkaloids as major phytochemicals. We investigated the antibacterial, anti-fungal, and anti-oxidant activity of pod methanolic extract. The extract was found equally effective against E. coli, S. pyogenes, and P. aeruginosa with MIC 100 μg/mL similar to the standard Ampicillin (MIC 100 μg/mL). C. albicans were found to be most susceptible to Vign unguiculata pods methanolic extract with a MIC of 250 μg/mL. The pod extract showed significant DPPH scavenging activity (IC₅₀=78.38±0.15) which suggests its antioxidant potential.     

A GmAOX2b antisense gene compromises vegetative growth and seed production in soybean

The alternative oxidase mediates the cyanide-resistant respiratory pathway in plant mitochondria. In non-thermogenic plants, the role of alternative oxidase in plant growth and development is not well understood. Soybean (Glycine max) lines carrying a GmAOX2b antisense gene had compromised vegetative growth and reproductive performance under typical glasshouse growth conditions. The reduction in vegetative growth was demonstrated by reduction in shoot height, the number of leaves per plant and the green leaf area. Antisense plants also had decreased pod formation and seed to pod ratios, which together led to a reduction in the number and total mass of seed produced. The negative effects of the antisense gene on pod set, seed set, ovule availability and total seed mass were primarily confined to the branches, rather than the main stem. The preferential effect of alternative oxidase suppression in the branches is discussed in relation to the reproductive potential of soybean under stress. Taken together, these results demonstrate that alternative oxidase provides the benefit of sustaining plant vegetative growth and reproductive capacity in soybean.     

CHANGES IN THE CONTENT OF GIBBERELLIN-LIKE SUBSTANCES IN RIPENING SEED AND POD OF LUPINUS LUTEUS

The amount of gibberellin-like substances in seed, pod, embryoand "endosperm" of Lupinus luteus in relation to their developmentwas studied by means of the rice seedling test. The amount of gibberellin-like substances per seed increasedremarkably at the first stage of development, when the growthof seed and pod was very slow, and attained its maximum at suchan early stage as the dry weight of seed reached a value ofonly 10 per cent and that of pod 28 per cent of their respectivemaximum levels. Changes in amount of gibberellin-like substancespresent in the pod were very closely related to the changesin growth of pod. Gibberellin-like substances equivalent to0.3 µg gibberellin A₃ per seed and 0.028 µg perpod were found at the 20th day after anthesis, and no activityin mature seed and 0.09 µg per pod at the 50th day. Noactivity was found in the embryo itself at all stages, indicatingthat the gibberellin-like substances in seed occur only in the"endosperm," i.e. in the tissues that will eventually form testain fully ripened stage. (Received December 18, 1962; )     

Inheritance of a one-seeded pod trait in peanut

Normally, the cultivated peanut (Arachis hypogaea L.) has predominantly 2 seeds per pod or more. Two seeds per pod are predominantly found in A. hypogaea L. subsp. hypogaea var. hypogaea (the botanical classification of the US runner and virginia market types) and in subsp. fastigiata var. vulgaris (the US spanish market type); whereas, predominantly 3 or more seeds per pod are found in subsp. fastigiata vars. fastigiata (the US valencia market type), peruviana (not marketed in the United States), and aequatoriana (not marketed in the United States), and in subsp. hypogaea var. hirsuta (not marketed in the United States). However, recently, predominantly 1 seed per pod selections were found within a Georgia cross population. Crosses involving the 1-seeded pod selection were made to determine its inheritance. The F(1), F(2), and F(3) data indicated that any 2 of 3 duplicate recessive genes designated, osp(1), osp(2), and osp(3), control the 1-seeded pod trait in peanut.     

Nonparametric approach to multitrait selection for yield in groundnut (Arachis hypogaea L.)

Summary Eight characters related to nitrogen fixation and pod development measured 30 days after flowering were evaluated for their correct grading of the relative yield performance of 17 genetically diverse lines of groundnut (Arachis hypogaea L.). Each line was assigned a high or low yield status based on its pod yield, shelling percentage, and 100-kernel weight. Seventeen character combinations were examined for their relative merit in correct identification of the yield status of lines. The character sets, nitrogenase activity alone or in combination with nitrogen percent or shoot weight identified the status of 77% of lines correctly. The extent to which various characters accounted for the variation in pod yield was also checked by multiple regression analysis. While the character combination, nitrogen percent plus leaf area explained 75% of variation in pod yield, nodule mass, nitrogenase activity, and leaf area occurred in some other combinations that explained yield variation to a lesser extent. These analyses point to the profitability of involving crop physiological traits such as leaf area and nitrogen percent in selecting for relative yield performance in groundnut.IARI Regional Station, Tutikandi, Simla 171004, IndiaNational Research Center for Groundnut, Timbawadi, Junagadh 362015, India     

Selenium speciation profiles in selenite-enriched soybean (Glycine Max) by HPLC-ICPMS and ESI-ITMS

Soybean (Glycine Max) plants were grown in soil supplemented with sodium selenite. A comprehensive selenium profile, including total selenium concentration, distribution of high molecular weight selenium and characterization of low molecular weight selenium compounds, is reported for each plant compartment: bean, pod, leaf and root of the Se-enriched soybean plants. Two chromatographic techniques, coupled with inductively coupled plasma mass spectrometry (ICPMS) for specific selenium detection, were employed in this work to analyze extract solutions from the plant compartments. Size-exclusion chromatography revealed that the bean compartment, well-known for its strong ability to make proteins, produced high amounts (82% of total Se) of high molecular weight selenospecies, which may offer additional nutritional value and suggest high potential for studying proteins containing selenium in plants. The pod, leaf and root compartments primarily accumulate low molecular weight selenium species. For each compartment, low molecular weight selenium species (lower than 5 kDa) were characterized by ion-pairing reversed phase HPLC-ICPMS and confirmed by electrospray ionization ion trap mass spectrometry (ESI-ITMS). Selenomethionine and selenocystine are the predominant low molecular weight selenium compounds found in the bean, while inorganic selenium was the major species detected in other plant compartments.     

Canavanine distribution in jackbean fruit during fruit growth

Summary Canavanine is an arginine analogue found in the seeds of many common legumes and is known to inhibit protein synthesis and growth in a number of organisms. Yet canavanine may comprise as much as 4% of the seed dry weight of the jackbean (Canavalia ensiformis).Canavanine is accumulated during earlier development in the pod, but disappears upon ripening. A corresponding increase in seed canavanine of about the same magnitude as the loss in the pod takes place during this latter time, but there is a subsequent significant increase of canavanine content of the seed after all detectable canavanine has disappeared from the pod. The first of these changes suggests synthesis of canavanine in the pod and transport into the seeds while the second one indicates a synthesis of canavanine in the seeds themselves, or possibly in the leaf or pod with rapid translocation to the seed.Canavanine was found to be at its highest concentration in the seed coats and pods when they were growing most rapidly and to gradually decline afterwards; however, the canavanine concentration of the seeds was found to be constant throughout fruit development.The pattern of canavanine mobilization in jackbean fruits was quite similar to the known pattern of total nitrogen mobilization typical of other leguminous fruits. This is consistent with a role as a nitrogen transport and storage compound.University of Tennessee, Department of Botany, Contribution N. Ser. No. 279.     

Management of peanut budnecrosis disease in groundnut through intercropping with cereal and pulse crops

Intercropping groundnut with sorghum at a 3:1 ration has given lower AUDPC (1018) with a mean pod yield of 1868 kg/ha, and was found significant in reducing the PBND (34.2%) compared to sole groundnut (AUDPC of 1545 mean pod yield of 1407 kg/ha, 52% PBND). In groundnut intercropped with pulses, groundnut + redgram (5:1) was found to be effective in reducing PBND to an extent of 10% and recorded higher equivalent pod yield of 2236 kg/ha with 1014 AUDPC compared to sole groundnut (AUDPC 1078, 63.44% PBND; mean pod yield of 1663 kg/ha). The higher incidence of PBND was recorded in the treatments involving greengram, blackgram and soybean and it was also reflected in realising higher values of AUDPC.     

寄主对豆野螟的药剂敏感性和体内解毒酶活性的影响

比较取食不同寄主植物的豆野螟MarucatestulalisGeyer幼虫对3种药剂敏感性的差异,及其体内4种解毒酶活性之间的差异。结果表明:取食不同寄主植物的豆野螟对高效顺反氯氰菊酯和灭多威的敏感性差异显著,豇豆>四季豆>扁豆;对茚虫威的敏感性差异不显著。取食不同寄主植物的豆野螟体内4种酶活性都发生了变化,乙酰胆碱酯酶(AChE)羧酸酯酶(CarE)和多功能氧化酶(MFO)活性之间存在显著差异,豇豆>四季豆>扁豆;但谷胱甘肽-S转移酶(GST)活性之间不具有显著差异。推测:取食扁豆的豆野螟体内产生对高效顺反氯氰菊酯和灭多威具有一定解毒作用的物质;而取食豇豆的豆野螟产生的某种物质对茚虫威具有一定的解毒作用,4种酶在其对茚虫威的解毒过程中起一定的作用。     

人工合成甘蓝型油菜特长角性状的遗传分析

以人工合成甘蓝型油菜特长角品系H218普通甘蓝型油菜中油821和MSP334为材料, 配制成两个杂交组合的各6个世代群体, 即P1、P2、F1、F2、B1、B2, 研究了全果长、果身长、果喙长3个角果性状的遗传特点。结果表明, 两个组合的全果长、果身长、果喙长在F2群体中近乎呈现连续正态分布, 显示为多基因控制的数量性状。两个组合的全果长广义遗传力为65.89%~70.77%、狭义遗传力为44.01%~46.78%, 基因数目均为5对; 果身长广义遗传力为60.14% ~ 63.38%、狭义遗传力为46.89%~47.38%, 基因数目均为6对; 果喙长广义遗传力为26.36% ~ 46.44%, 狭义遗传力为18.08%~37.87%, 基因数目均为2对。基因效应初步分析表明, 两个组合的3个性状基因效应均符合加性-显性二基因互作模型, 存在显著的上位性效应。两个组合的全果长、果身长、果喙长加性效应、显性效应都很重要, 全果长、果身长的加性效应大于显性效应, 果喙长显性效应大于加性效应。     

A 9 × 9 diallel analysis in peanuts (A. hypogaea L.): Flowering time,tops' weight,pod yield per plant and pod weight

Summary Four quantitative traits were studied by analysing F₂ data derived from a 9 × 9 diallel cross utilizing widely divergent, inbred, erect cultivars of peanuts, A. hypogaea. Bidirectional dominance was found in the traits total pod yield per plant and number of days from planting to first flower; in pod size, the alleles giving small pods were consistently dominant and for high tops' weight, dominance and overdominance were found. The high heritability of pod yield/plant (0.79) indicates that breeding for higher yield/plant can succeed if large F₂ populations are grown and rigorous visual selection combined with progeny testing are employed. The genetic correlations of pod yield/plant with other traits were low. Breeding for plants with large (jumbo) pods can be aided by the fact that they are homozygous recessive, or nearly so. Simultaneous breeding for high yields and large pods is possible: there was a positive (but low) genetic correlation between the two (0.16). A modification by which less biased estimates of the number of effective factors can be obtained and a possible relationship between bidirectional dominance and genic interaction were proposed.     

A Pod Leakage Technique for Phloem Translocation Studies in Soybean (Glycine max [L.] Merr.)

Radioactive photosynthetic assimilates, translocated to a soybean (Glycine max [L.] Merr. `Fiskeby V') pod can be measured directly by excising the stylar tip of the pod under 20 mm ethylenediaminetetraacetate solution (pH 7.0) and allowing the material to leak into the solution. Pods at the source node received approximately 50% of the ¹⁴C exported from the source leaf to the pod and leaked approximately 1 to 3% of this into the solution. More than 90% of the ¹⁴C that leaked from the pods was found in the neutral fraction and, of this, about 93% was in sucrose. Fifteen amino acids were identified in the leakage including: alanine, arginine, asparagine, γ-aminobutyric acid, glutamine, glycine, histidine, isoleucine, leucine, lysine, phenylalanine, serine, threonine, tyrosine, and valine. The majority of the ¹⁴C in the basic fraction was found in serine (30%) and asparagine (23%). The inorganic ions K, Ca, P, Mg, Zn, and Fe were found in the leakage component. Nitrate was not detectable in the collected leakage solution. The absence of NO₃⁻ and the large proportion of the label in sucrose suggest a possible phloem origin for most of the material. The technique provides an uncomplicated, reproducible means of analyzing the material translocated into and through the soybean pod, as well as following the time course of label arrival at the pod.     

Effect of cocoa pod age on egg distribution and egg parasitism of the cocoa pod borer in Malaysia

The effects of pod age on oviposition, and on egg and larval survival of the cocoa pod borer (CPB), Conopomorpha cramerella (Snellen), were investigated. CPB were allowed to oviposit on a batch of 50 pods for a period of 7 days over several exposure dates. Numbers of CPB eggs/pod and survival to larval emergence from the pods were recorded. Pods were harvested when ripe and analyzed for larval survival within the pod. The oviposition pattern varied with pod age. Older pods less than 7 weeks before ripening (WBR) were preferred, suggesting greater nutritional value or chemical attraction of the older pods. The proportion of eggs parasitized by Trichogrammtoidea bactrae fumata Nagaraja (TBF), the number of eggs lost and the proportion surviving to larval emergence from the pod were independent of pod age. Egg parasitism was low, implying that TBF was not an effective natural enemy. Mass-releases of TBF should be intensified during cropping periods with higher proportions of susceptible pods (<10 WBR). Survival of larvae in the presclerotic layer (preSCL) was high and independent of pod age. Larval mortality at the SCL (sclerotic layer) was dependent on pod age and was high in older pods. Larval density influenced the survival of larvae inside the pod and was dependent on pod age. Larval mortality associated with SCL hardness and thickness is one of the criteria for the selection of CPB resistant cocoa clones.     

Modified behaviour in nucleopolyhedro virus infected field bean pod borer, Adisura atkinsoni and its impact on assessing the field efficacy of NPV

When nucleopolyhedro virus of A. atkinsoni was applied at 250 LE/ha, there was no significant difference between the viruses treated and control plots with regard to the total number of live larvae feeding outside the pod. However, due to changes in behaviour in NPV infected A. atkinsoni by way of coming out of the pod, there was a significant difference when counts were taken with regard to total number of larvae found feeding inside the pod. Both endosulfan at (0.07%) and virus (125 LE/ha) in combination with endosulfan (0.035%) significantly reduced the larval population of A. atkinsoni and Sphaenarches anisodactylus. There was no significant difference between the virus and control plots with regard to percentage of pod damage. However, when the yield was assessed based on the seed weight, there was significant difference.