N-Dimethylamino Succinamic Acid (B-Nine) as a Potential Aid in Improvement of Medicago sativa L.

The influence of N-dimethylamino succinamic acid (B-nine) on lucerne plants cv. IGFRI-244 was investigated. B-nine (a growth regulant) was sprayed as a foliar sprays, employing 10, 100, 250, 500, 1000 and 5000 ppm alongwith water spray as control, and the effects were observed on plant growth, flowering, nutritive constituents and seed yield of the crop. Plant height was reduced from 6.19 to 26.85 % in various concentrations of B-nine being highest retardation in 5000 ppm, whereas 250 ppm produced more branches and leaves with dense foliage in comparison to control and other treatments. Delayed flowering by 2–15 days with significant increase in seed yield and 1000 seed weight B-nine bein maximum seed yield in 250 ppm. However, total seed yield was increased by 4.16 to 24.76 per cent over unsprayed control plants. Among the treated levels of B-nine, 250 ppm also gave higher values for Carbohydrate, IVTDMD in shoot of lucerne plants with considerable decreased in 5000 ppm. NDF condent decreased progressively with increased concentration of B-nine but always lesser than the value of IVTDMD.     

Fasciation in chickpea: genetics and evaluation

Summary A spontaneous fasciated mutant was detected in the chickpea cv. Amethyst. It was characterised by broad, strap-like stems, irregular leaf arrangement and clustering of pods towards the stem apices. F₂ and F₃ segregations showed that fasciation was controlled by a single, recessive gene for which the symbol fas is proposed. Field trials comparing the fasciated mutant with its non-fasciated isoline showed that fasciation was associated with lower yield, larger seeds, delayed flowering and increased lodging.     

Induction of male flowering in gynoecious cucumbers (Cucumis sativus L.) by silver ions

Summary Silvernitrate (AgNO₃) and silverthiosulphate (Ag(S₂O₃)₂ ^3-) effectively induced male flowering in many nodes of 7 gynoecious cucumber genotypes in 3 glasshouse trials. A single spraying of the plants in the first true leaf stage with 3 mM Ag⁺ as Ag(S₂O₃)₂ ^3- or AgNO₃ (500 ppm) yielded many more staminate flowers than GA-3 (1500 ppm) and almost as many as 3 consecutive sprayings of GA-4/7 (50 ppm).Male flowering started about 3 weeks after treatment and lasted for a period of up to 4 weeks thereafter. Plants treated with silver ions did not elongate and grew normally; effective concentrations of AgNO₃ proved phytotoxic only in poor growing conditions, while Ag(S₂O₃)₂ ^3- never gave deleterious side-effects. Even very strongly female lines can be induced to male flowering with silver ions, thus increasing the feasibility of large scale seed production of gynoecious × gynoecious cucumber hybrids.     

Gynoecious sex expression and stability in cucumber (Cucumis sativus L.)

Summary Results indicated that gynoecious stability in the F₁ is governed by partial dominance. The degree of gynoecious stability is dependent upon genotypes, stages of plant for AgNO₃ application and number of sprays. Depending upon the genotypes, the one-true-leaf stage and one spray of 250 ppm AgNO₃ showed more gynoecious stability in the F₁. Twice application of AgNO₃ at the two-true-leaf stage produced the maximum number of male flowers. Plants exposed to light for longer time (10.00 h) after AgNO₃ application produced less flowers than when exposed for shorter time (15.00 and 20.00 h).Present address: Division of Vegetable Crops, Indian Agricultural Research Institute, New Delhi-110012, India.     

Effect of GA, CCC and B-9 on Morphophysiological Characters and Yield of Kidney Beans (Phaseolus vulgaris L.)

A pot and 2 successive seasons field experiments were conducted on bean, by spraying 25,50 or 100 ppm GA, 100, 250 or 500 ppm of either CCC or B-9, one month after sowing. Results showed that:
GA induced stem elongation and thinning through cell elongation and decrease of both of ground tissue cell-size and vascular cylinder cell layers in the stem. On the other hand, CCC and B-9 led to stem shortening and thickening, as a consequence of increased number of cell layers leading to widening the vascular cylinder of the stem.
Leaf area was much more increased by CCC and B-9 than by GA.
GA increased amylase activity and had no effect on invertase, meanwhile CCC and B-9 mostly decreased the former's and increased the latter's enzyme activity, 30 days after spraying.
GA and CCC increased number of seeds/pod, while B-9 had no effect on this character.
CCC and B-9 increased pod number/plant, specific seed weight, leading to increment of seed yield/plant, while GA had no effect on these characters.     

The association of sexuality with plant traits and tuber yield in white yam

Summary One 3-to 5-year clonal and two recent seedling-derived populations of white yam cultivars were grown and studied for the association of sex, flowering intensity, number of fruits and seed yield with vegetative characters and tuber yield. Yield was lowest in non-flowering plants and increased in the following order: male, monoecious and female plants; with females yielding almost twice as much as the non-flowering plants. The plants produced from small tuber setts, with higher leaf virus infection, low plant leafiness either had low flowering intensity, fewer fruits and seeds or even failed to flower. The sequence and timing of vegetative and reproductive processes in relation to the difference in yield between male and female plants is discussed. There is a strong indication that the intensity of flowering and fruiting is lower in plants from previous vegetative propagation compared to recent seedling-serived clones.     

Promotion of pistillate flowering inCucurbita by 2-chloroethylphosphonic acid

Summary All accessions tested of four cultivated species ofCucurbita responded to seedling treatment with 250 ppm 2-chloroethylphosphonic acid by developing only pistillate flowers for an extended period. This growth regulator is a promising means of facilitating hybrid seed production of squash. A similar treatment did not induce flowering of wild species ofCucurbita that were vegetative under the environmental conditions of the experiment.Approved by the Director of the New York State Agricultural Experiment Station for publication as Journal Paper No. 1737.     

Effects of Thiourea, Thiamine and Ascorbic Acid on Growth and Yield of Maize (Zea mays L.)

Three chemicals, viz., thiourea, thiamine and ascorbic acid capable of potentiating-SH turnover, were tested with the objective to improve growth and productivity of maize. Thiourea was tested as seed-soaking and foliar-applied treatments as also in combination. Thiamine and ascorbic acid were tested as foliar sprays alone. Foliar treatments were applied at vegetative stage (30 and 45 days after sowing).
The results of the field experiment showed that seed soaking with thiourea (500 ppm) tended to improve grain yield (13.4 per cent over control), but improvement in biological yield was significant. However, seed soaking plus foliar treatment of thiourea significantly increased both biological and grain yields, besides causing significant improvement in leaf area index and number of green leaves plant^-1. The increase in grain yield ha^-1 was of the order of 34.6 per cent over control.
It was further noted that foliar sprays of thiourea (1000 ppm), thiamine (100 ppm) and ascorbic acid (100 ppm) significantly increased leaf area index, number of green leaves plant^-1 and biological yield ha^-1. These treatments also significantly increased grain yield ha^-1 by 40.6, 20.2 and 26.3 per cent, respectively over control. Improvement in maize yield with thiourea, thiamine and ascorbic acid treatments appeared to have resulted from increased photosynthetic efficiency and canopy photosynthesis on account of the biological activity of -SH group. It was also apparent that leaf senescence was delayed under the influence of these chemicals. It is therefore suggested that thiourea, thiamine and ascorbic acid are the potential bioregulators for improving photosynthetic efficiency and grain yield of maize and possibly other cereals, and that thiourea, a sulphydryl compound, holds considerable promise in this context.     

Development of early-flowering Kabuli chickpea with compound and simple leaves

Terminal drought is a major constraint to chickpea (Cicer arietinum L.) production. Autumn sowing and early flowering have been suggested as ways to benefit from the winter rains in short rainy seasons under dryland cropping. High‐yielding, late‐flowering, simple‐leafed (slv/slv) chickpea cultivars with good field resistance to Ascochyta blight have been bred recently. Changing plant architecture, by altering leaf shape, may affect agronomic performance. As no information is available on the effect of leaf shape on phenology and seed yield, this study was aimed at: (i) introducing the simple leaf trait into an early‐flowering chickpea background; (ii) comparing the grain yield of the two leaf types in early vs. late flowering backgrounds and (iii) producing breeding lines combining early flowering, large seeds and Ascochyta tolerance with both leaf types. Hybrid progeny were studied from the cross of ‘Sanford’ (slv/slv) and ICC7344, (compound, SLV/SLV). Four early‐podding, F₈ breeding lines were selected with either simple or compound leaves. In three different field experiments under dryland conditions (334–379 mm), they yielded ca. 1.4 t/ha as compared with 1.0 t/ha in the standard Israeli ‘Yarden’ on one site, but no significant differences in yield were obtained in the other two experiments.     

木醋液浸种对西葫芦种子萌发和幼苗生长的影响

为研究木醋液浸种处理对西葫芦种子萌发和幼苗长势的影响,笔者广泛查阅相关资料,用100、300、500倍的稀释木醋液浸种6 h,并用同体积蒸馏水同时间浸种作为对照进行研究,调查分析在光照培养箱内种子萌发和幼苗生长的情况。结果表明：使用木醋液浸种,对于西葫芦的发芽势、发芽率、幼苗芽长、幼苗主根长、百苗鲜重、百苗干重,以及活力指数都有影响。使用不同浓度的木醋液浸种,对西葫芦种子各项发芽指标和幼苗长势的影响不同;使用100倍稀释木醋液浸种,幼苗长势形成最高峰值,活力指数比蒸馏水浸种的对照提高9.01%,鲜重、干重、主根长分别比对照增加13.47%、9.81%、15.79%,产生显著差异;使用100倍稀释木醋液浸种处理对发芽势有一定的促进作用,对芽长、发芽率、发芽指数影响不显著。说明木醋液浸种可促进根系生长、鲜重和干物质积累增加,提高活力指数,幼苗长势更强,可应用于西葫芦种子播前处理。     

The relationship of stem and seed yields to flowering phenology and sex expression in monoecious hemp (Cannabis sativa L.)

Flowering phenology and sexual dimorphism are two major features that affect stem and seed production in hemp (Cannabis sativa L.), a short-day naturally dioecious plant. The sowing time is of primary importance because it affects flowering time and thereby influences stem yield. In spite of their unstable sexual phenotype, monoecious cultivars facilitate the harvest of both stems and seeds by reducing crop heterogeneity. The main objective of this paper was to determine the stem and seed yields for five monoecious hemp cultivars in relation to their flowering phenology and sex expression. Sowing was carried out on five distinct dates during 2007 and 2008 at two sites in Belgium. The duration from sowing to flowering in days, both stem and seed yields and the seed harvest index decreased when sowing was postponed from mid-April to the end of June. The stem and seed yields from the mid-April sowing (approximately 12.5 and 1.9 t ha⁻¹, respectively) were within the ranges that were reported for fibre and both fibre and seeds production, respectively, in monoecious hemp. No interaction was observed between the sowing date and cultivar for both yields. Sex expression varied among cultivars, indicating that it might be selected, and was partly linked to earliness. Stem yields were lowest in the earliest cultivar (Uso 31) and highest in the latest one (Epsilon 68) while seed yields were lowest in the most masculinized and earliest cultivar (Uso 31) and highest in the most feminized and early (Fedora 17) or mid-early (Felina 32) ones. Both stem and seed yields correlated best with the duration from sowing to full female flowering or from sowing to the end of male flowering.According to our results, harvesting the seeds in addition to the stems in monoecious hemp requires early sowing and the selection of feminized early or mid-early cultivars, earliness depending on the climatic conditions in the cultivation area. Therefore, it might be agriculturally valuable to take sex expression into account in addition to earliness during the selection of cultivars that are adapted to a dual purpose.     

Analysis of ATPase and succinic dehydrogenase in F1 hybrids of rice (Oryza sativa L.)

Summary Activities of ATPase and succinic dehydrogenase were assessed in three F₁ hybrids of rice and their parental lines during boot leaf stage, flowering, on 10th and 20th days after flowering. ATPase activity showed increase at the flowering and on 20th day after flowering. Succinic dehydrogenase activity continued to rise till 10th day after flowering and declined on 20th day after flowering. Hybrids with high yield were generally endowed with more positive heterosis for these two enzymes. Correlation coefficient of grain yield per panicle was significantly positive with ATPase activity at all the stages studied. Heterosis for ATPase activity might serve a reliable criterion for the selection of efficient F₁ combinations.     

A quinclorac sensitive lethality rice mutant: its discovery,genetics and potential application

In this study, we reported a quinclorac‐sensitive rice natural mutant M4017, derived from an indica restorer line 4017 of three‐line hybrid. The mutant could be killed at three‐leaf stage by quinclorac at 175 mg/l or higher, a dosage that is recommended for monocot herbs control. The mutant at flowering stages can also be effectively killed by quinclorac at 1.25–1.50 g/l or higher, which is safe for its F₁ hybrids and all other normal varieties. Genetic analysis, using the F₁, F₂ and BC₁ populations derived from this mutant and other often‐used varieties, revealed that quinclorac sensitivity/lethality was controlled by a single recessive gene, which was named quin1. This mutant has a potential application in false hybrid seed removal or mechanized production of hybrid seeds.     

Effectiveness of Ethrel as a Male Gametocide in Pearl Millet and its Influence on Ergot

In field and greenhouse experiments Ethrel (2-chloroethyl phosphonic acid) was tested for its male garnetocidal effects on pearl millet (Pennisetum americanum) and its subsequent effects on ergot development. Application of Ethrel at 2000 ppm at late boot or early protogyny was the most effective for inducing male sterility in the hybrid, EJ 104. Female fertility in a male sterile line, however, was not affected by Ethrel treatment. Ethrel at 2030 ppm applied at ihe late boot stage resulted1 in partial paniele exsertion, and reduced plant height anc. panide length. In vitro Ethrel (2000 ppm) completely inhibned pollen germination but did not affect germination of conidia of Claviceps fusiformis, the causal agent of ergot of pearl millet. Ergot resistance or susceptibility in pearl millet lines was not affected., probably because Ethrel could not induce complete male sterility.     

Shading of plants facilitates selection for powdery mildew resistance in Squash

Summary Powdery mildew development was assessed on squash (Cucurbita pepo) plants of a susceptible cultivar, a resistant accession, their F₁, and their F₂ in an early summer planting in the field, covered or not covered with a shading net. Three reaction types were observed: susceptible, powdery mildew on stems and on both, the upper and lower leaf surfaces, as in the susceptible parent; resistant, no powdery mildew on leaves or stems, as in the resistant parent; and partially resistant, powdery mildew on upper leaf surfaces only, as in the F₁. Disease presence on the stem was associated with susceptibility. Shading hastened the appearance of powdery mildew and increased the severity of infection on partially resistant and susceptible plants, facilitating identification of resistant individuals in the F₂ population.Contribution No. 1613-E from the Agricultural Research Organization, Bet Dagan, Israel     

Characterization,inheritance, and molecular study of opaque leaf mutant in mungbean (<Emphasis Type="Italic">Vigna radiata</Emphasis> (L.) Wilczek)

Chlorophyll-deficiency mutants are useful as genetic markers and as materials for studying the photosynthesis process. We characterized the inheritance of the gene controlling an opaque leaf (OL) trait in mungbean (Vigna radiata (L.) Wilczek). An F₂ population was developed from the cross between the OL mutant and ‘Berken’, an Australian mungbean cultivar, to study inheritance and molecular tagging. The population was advanced by selfing to produce F₅ lines from which two normal lines and two OL lines were randomly chosen to study chlorophyll content, seed growth and development, and seed cell morphology. The chlorophyll content in opaque leaf was lower than normal and thus was expected to have lower photosynthetic activity. This resulted in yellowish and shrinking pods and seeds within 15 days after flowering, while those from normal plants extended their growth up to 18 days. The cotyledon transfer cells of the OL plants deformed at 12 days and deteriorated at 14 days after flowering. The OL trait was controlled by a single recessive ol gene which was independent from the genes controlling petiole color and growth habit. We used 193 AFLP primer combinations to tag this gene and found that the marker AGG/ATA was linked with the ol gene at a distance of 3.4 cM.     

Different sex phenotypes of Cucumis sativus L. and C. melo L. and their endogenous gibberellin activity

Summary Gibberellins were extracted from seeds and green plants of different sex types of the closely related species Cucumis sativus L. (cucumber) and C. melo L. (muskmelon). Both seeds and green plants of monoecious and andromonoecious lines of C. sativus contained significantly higher gibberellin levels at all growth stages tested than did a gynoecious line. Gibberellin activity in the monoecious and andromonoecious C. sativus line reached a maximum at the growth stage corresponding to flower differentiation at cotyledonary and first leaf axils. Vernalization of seeds of gynoecious plants resulted in increased male tendency correlated with increased gibberellin activity. In contrast, monoecious and andromonoecious lines of C. melo were gibberellin deficient relative to hermaphroditic and gynoecious lines.Journal Article No 5534 from the Michigan Agricultural Experiment Station. This work was supported by a grant from the Herman Frasch Foundation.     

Inheritance of resistance to angular leaf spot (Isariopsis griseola Sacc.) in french bean (Phaseolus vulgaris L.)

Summary Angular leaf spot (Isariopsis griseola Sacc.) is a serious disease of French bean in the hills of India and 40 to 70 per cent of the green pods are damaged and rendered unmarketable. Crosses were made between PLB 257, (Phaseolus coccineus L.), a red flowering pole tope, resistant to angular leaf spot, and Contender (Phaseolus vulgaris L.), a highly susceptible commercial cultivar. Studies of the F₁, F₂, and F₃ progenies indicated that PLB 257, carries a recessive gene imparting resistance to angular leaf spot.     

GA4+7 plus BA enhances postproduction quality in pot tulips

Previously we reported that postproduction quality of pot ‘Seadov’ tulip (Tulipa gesneriana) was significantly increased by GA₄₊₇ plus BA in a manner dependent on the concentration and stage of flower development at application. In these experiments, we extended the survey to 20 tulip cultivars to further evaluate the effects of GA₄₊₇ plus BA sprays for enhancing postproduction flower and leaf quality. The senescence symptom of the cultivars fell into three categories: wilting, wilting-abscission (abscission shortly after tepal wilting) and abscission (abscission without wilting), with the majority of the cultivars belonging to the wilting and wilting-abscission categories. Pots bearing six plants were sprayed with a range of GA₄₊₇ plus BA concentrations at marketable stage and placed in a simulated consumer environment (SCE). GA₄₊₇ plus BA significantly enhanced individual flower and postproduction longevity, but the effect was dependent upon the senescence category of the cultivar. In general, GA₄₊₇ plus BA increased individual flower and postproduction longevity of wilting-type cultivars at concentrations above 10 mg L^?1, while longevity of wilting-abscission-type cultivars was only enhanced by 50 mg L^?1. Abscission-type cultivars were not affected by any concentrations of GA₄₊₇ plus BA. Regardless of floral senescence category, leaf yellowing was significantly reduced by GA₄₊₇ plus BA sprays in those cultivars showing postproduction leaf yellowing. GA₄₊₇ plus BA did not induce leaf and stem elongation in most cultivars. Only ‘Yellow Baby’, the shortest cultivar, showed elongation of stem and leaf by GA₄₊₇ plus BA at concentrations above 25 mg L^?1. Spray applications of GA₄₊₇ plus BA can be useful to enhance flower and leaf quality in pot tulips.     

Investigations on F1 and F2 hybrids between Brassica oleraceae Var. Acephala and Raphanus sativus

A cross was made between B. oleraceae var. acephala and R. sativus. The use of a piece of cotton soaked with the growth regulator, N-m-tolyphthalamic acid at 100 ppm and attached to the pedicel at the time of pollination resulted in set of several pods with one viable seed. The hybrid kale x radish appeared vegetatively intermediate between the parents except for the flower color which resembled the radish. The F₁ plant propagated asexually and maintained under screen isolation cages with pollinating insects for a period of four years yielded only one viable F₂ seed. The single F₂ plant obtained, an allotetraploid, failed to yield any fertile seeds through selfing. Backcrossing of this F₂ plant to the radish has yielded two seeds.Department of Horticulture, Michigan State UniversityWith 7 figuresJournal article No. 2923. From the Michigan Agricultural Expreriment Station.