Number Of Female Flowers Research Articles

Genetic diversity of Jatropha curcas L. genotypes: a potential biofuel crop in Bangladesh

Jatropha curcas L. is a potential biofuel crop grown in the tropics and subtropics. The present study was conducted to enumerate the genetic diversity of 17 morpho-agronomic traits of 45 Jatropha genotypes from Bangladesh during 2015–2017. Analysis of variance revealed sufficient genetic variation among the genotypes for all the traits. High broad-sense heritability coupled with high genetic advance as a percentage of the mean were observed for seed yield per plant and related traits. Correlation coefficients indicated that total number of inflorescences, number of male flowers per inflorescence, number of female flowers per inflorescence, number of fruits per inflorescence, number of seeds per inflorescence, weight of mature fruits per inflorescence, weight of dry fruit per inflorescence and weight of dry seeds per inflorescence were highly correlated with seed yield per plant. The first four principal components explained 81.2% of the total variation. Cluster analysis based on Euclidean distance indicated the highest intra-cluster distance in cluster II and the highest inter-cluster distance between clusters II and VI. Based on this study, it is suggested that hybridization of parents between clusters II and VI will produce noble hybrids that will increase the potential for biofuel production.

Morphological characterization and transcriptome analysis of pistillate flowering in pecan (Carya illinoinensis)

Pecan [Carya illinoinensis (Wangenh.) K. Koch] is a famous high grade dry fruit, oil tree species and excellent tree species for both timber and fruit. Pecan is a monoecious plant, and the formation and number of female flowers directly determine the pecan yield. In this work, to illuminate the molecular mechanism of floral formation in pecan, scanning electron microscopy was employed to distinguish the developmental stages of female flower. Three flower buds and two flowering stages were collected for high throughput RNA sequencing. 65,680 unigenes were generated with 41, 806 differentially expressed genes annotated. Genes involved in hormone signaling, carbon and nitrogen metabolism showed significant differential expression during the floral developmental process. The MADS-box gene family was analyzed in depth, the six type-I genes were not expressed in the FL2 stage, while most type-II genes were highly expressed in the late flower stages. In order to explore the regulation mechanism of pecan flowering, we selected 299 floral-related genes to construct gene co-expression network. The photoperiod pathway genes LHY, PHYA, ELF3 and the gibberellin metabolic pathway gene DELLA proteins function as key roles in floral pathways. We also identified four hormone metabolic pathway genes correlated (SAUR15, IPT1, IAA29, and ARF2) with CiMADS5, CiMADS8, CiMADS9, CiMADS20, and CiMADS39. Furthermore, the expression patterns of 16 unigenes involved in flower development were validated using quantitative real time PCR. These findings are of great significance for further understanding of the molecular basis for reproductive development in Carya Nutt species.

Growth and yield of Jatropha curcas L. (Euphorbiaceae) plants cultivated in different spacing and treated with kinetin

Recommendations for J. curcas plants were studied for adequate crop spacing, and to increase the number of female and hermaphrodite flowers and fruit yields. The study was carried out in an experimental field in Brazil,using four-year-old adult plants in a 5 x 3 factorial in a completely randomized design with three replications. Treatments included five doses of the growth regulator kinetin (0, 3, 6, 9 and 12 mg L-1 at the volume of 330 ml per plant) in a single application to six plants and three planting spaces (3×3, 3×2, 3×1 m). The results showed that the applied kinetin doses did not interfere in the production index of J. curcas, but population density exerted a significant influence on the vegetative and reproductive development of the J. curcas plants in the 3x3 spacing, where competition for essential growth resources (water, light and nutrients) seems to have been less intense and the plants were more vigorous. Cropping J. curcas plants in 3 × 3 spacing is recommended to obtain vigorous plants with a high number of branches, inflorescences and high grain yield. Applying kinetin at concentrations lower than 12 mg L-1 did not interfere in the sexual expression of J. curcas flowers. Further studies with higher kinetin doses in 3 × 3 m spacing are necessary to elucidate and recommend new management practices.

Phenological and Morphological Traits of Important Hazelnut Cultivars in North West Bosnia

The paper presents the results of the analysis of phenological and morphological characteristics of 3 hazelnut cultivars present in the production plantation in the north-western Bosnia and Herzegovina. The 'Rimski', 'Istarski dugi' and 'Tonda Gentile Romana' cultivars served as research material. Blooming time ranged from December to March. For all cultivars, the occurrence of dichogamy, precisely protandry, was observed. The longest flowering period of both male and female flowers was found in the 'Tonda Gentile Romana' cultivar. The 'Rimski' cultivar had the highest fruit weight (3.04 g). 'Tonda Gentile Romana' had the highest kernel weight (1.50 g). The highest kernel percentage (49%) was found in 'Istarski dugi'. The length of male catkins ranged from 21.73 cm to 29.76 cm. Statistically significant differences among cultivars were found for the following traits: the length of male catkins, the number of female flowers in glomeruli, and the number of nuts on a fruiting shoot. The 'Istarski' cultivar had the highest average length of male catkins (29.76) and the highest number of female flowers in the glomeruli (7.32). 'Tonda Gentile Romana' had the highest number of fruits (20.93) on the shoots. All three cultivars have proven to be good varieties in terms of phenological and morphological characteristics, so they can be recommended for intensive production of this nut crop.

Morphological, Transcriptomic and Hormonal Characterization of Trimonoecious and Subandroecious Pumpkin (Cucurbita maxima) Suggests Important Roles of Ethylene in Sex Expression.

Sex expression is a complex process, and in-depth knowledge of its mechanism in pumpkin is important. In this study, young shoot apices at the one-true-leaf stage and 10-leaf stage in Cucurbita maxima trimonoecious line ‘2013–12’ and subandroecious line ‘9–6’ were collected as materials, and transcriptome sequencing was performed using an Illumina HiSeqTM 2000 System. 496 up-regulated genes and 375 down-regulated genes were identified between shoot apices containing mostly male flower buds and only female flower buds. Based on gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, the differentially expressed genes were mainly enriched in the ethylene and auxin synthesis and signal transduction pathways. In addition, shoot apices at the 4-leaf stage were treated with the ethylene-releasing agent 2-chloroethylphosphonic acid (Ethrel), aminoethoxyvinyl glycine (AVG), AgNO3 and indoleacetic acid (IAA). The number of female flowers up to node 20 on the main stem of ‘2013–12’ increased significantly after Ethrel and IAA treatment and decreased significantly after AVG and AgNO3 treatment. The female flowers in ‘9–6’ showed slight changes after treatment with the exogenous chemicals. The expression of key genes in ethylene synthesis and signal transduction (CmaACS7, CmaACO1, CmaETR1 and CmaEIN3) was determined using quantitative RT-PCR, and the expression of these four genes was positively correlated with the number of female flowers in ‘2013–12’. The variations in gene expression, especially that of CmaACS7, after chemical treatment were small in ‘9–6’. From stage 1 (S1) to stage 7 (S7) of flower development, the expression of CmaACS7 in the stamen was much lower than that in the ovary, stigma and style. These transcriptome data and chemical treatment results indicated that IAA might affect pumpkin sex expression by inducing CmaACS7 expression and indirectly affecting ethylene production, and the ethylene synthesis and signal transduction pathways play crucial roles in pumpkin flower sex expression. A possible reason for the differences in sex expression between pumpkin lines ‘2013–12’ and ‘9–6’ was proposed based on the key gene expression. Overall, these transcriptome data and chemical treatment results suggest important roles for ethylene in pumpkin sex expression.

Effect of foliar spray of GA3 and NAA on sex expression and yield of bitter gourd

A field experiment was conducted at the Plant Physiology field of Horticulture Research Center, BARI, Gazipur during two consecutive years of kharif 2014 and 2015 to assess the effect of GA3 and NAA on sex expression, yield and yield components of bitter gourd (Momordica charantia L.) var. BARI Karola-1. Eeleven treatments comprising five concentrations each of gibberellic acid (50, 100, 150, 200 and 300 ppm) and naphthalene acidic acid (50, 100, 150, 200 and 300 ppm) along with distilled water considered as control were evaluated in randomized complete block design with three replications. Gibberellic acid (GA3) and Naphthalene acidic acid (NAA) were sprayed at 4 leaf stage; second spray was done at 35-38 DAS and third spray done at flowering stage. All the treatments improved the flowering and yield characters over control. Foliar spray of NAA @ 150 ppm and 200 ppm was found better in terms of sex expression, yield and yield attributes of bitter gourd as compared to control and other treatments. Spray of NAA @ 150 ppm gave the lowest number of male flowers and the highest number of female flowers thereby produced the lowest sex ratio (male:female). Number of fruits/plant, individual fruit weight and fruit yield/plant were also found maximum from NAA 150 ppm. Maximum fruit yield was recorded with the application of NAA @ 150 ppm. Spraying of NAA @ 150 ppm gave the maximum gross return and net return with the highest BCR of 3.17.
 Bangladesh J. Agril. Res. 44(2): 281-290, June 2019

Plant growth regulators: One of the techniques of enhancing growth and yield of Bangladeshi local cucumber variety (Cucumis sativus)

Cucumber (Cucumis sativus) is becoming an essential part of the regular food menu for both health cautiousness and its dietary value over other foods. Availability of high yielding cucumber variety is one of the major obstacles for cucumber production in Bangladesh. Plant growth regulators (PGRs) play a significant role to alter the various type of physiological and morphological characters in cucumber. In this research, Bangladeshi local cucumber variety ‘Baromashi’ was used to observe the effect of PGRs on growth and yield-related characters. Four different treatments (Control: untreated plant, T1: maleic hydrazide 200 ppm, T2: ethephon 300 ppm and T3: NAA (1-naphthaleneacetic acid) 18 ppm) were used. Application of PGRs showed an increased number of primary and secondary branches however, negative effect on stem length and node for the first flower was also observed. PGRs showed the opposite effect on the time required for the first flowering where male flower needed more time and female flower required less time compared to the untreated plants. In the case of fruit-related characters, PGRs possessed positive effect and ethephon 200 ppm showed the best result among the treatments. Total yield might be directly related to the number of branches as well as with the number of female flowers in local cucumber variety.

Floral structure and development in Alchornea sidifolia (Acalyphoideae) and the evolution of wind pollination in Euphorbiaceae

Most Euphorbiaceae are insect pollinated, but in Acalyphoideae a considerable number of species are wind pollinated and generally have inconspicuous monochlamydeous flowers with red styles and multifid or laciniate stigmata. Alchornea is within the basal alchorneoid clade, and its flowers are more conspicuous in the group. The aim of this study was to investigate the ontogeny, anatomy and vasculature of flowers of Alchornea sidifolia Mull. Arg., species from the Alchorneoids clade, a basal clade sister of the “core acalyphoid,” in order to find structural aspects related to wind pollination. Flowers and buds of A. sidifolia were embedded in Paraplast and sectioned with a rotary microtome for analysis under light microscopy. SEM was performed for additional structural and ontogenetic data. Alchornea sidifolia is dioecious and has morphologically and functionally unisexual flowers which only share a monochlamydeous, tetramerous perianth, organized in a single whorl of sepals. In the male flower, calyx begins as a ring on the floral meristem in a congenital connation, but in the female one, the calyx has a late synsepaly. Pistillodes and staminodes are absent in the male and female flowers, respectively. The filaments of the stamens are connate at the base for a short extant and free toward the apex. The gynoecium is syncarpous, and the ovary is mostly synascidiate with a short symplicate zone and two long stigmata. Our results highlight the development of features of the inflorescence and flowers of A. sidifolia which in comparison with insect-pollinated Euphorbiaceae display a set of features which are typically associated in many other unrelated angiosperm lineages with the evolution of wind pollination, such as dioecy, production of a higher number of flowers in the male inflorescences than the female inflorescences, unisexual flowers with reduced perianth and no nectaries, male flowers with a variable number of stamens and female flowers with extensive stigmatic receptive surface. We also discuss the presence of two carpels in Alchornea, when most Euphorbiaceae and many other Malpighiales have three, and its relationship with the wind pollination.

Development and Productivity of Jatropha curcas Plants Treated With Growth Regulators

The objective of the present work was to evaluate the effect of plant growth regulators (PGR) on the vegetative development and productivity of Jatropha curcas plants. A field experiment was conducted at the Goiás State University, Brazil, using two-year-old J. curcas plants planted with spacing of 3 × 2 m, using foliar applications of two PGR—trinexapac-ethyl and prohexadione-Ca. A randomized block design was used with four treatments (trinexapac-ethyl at 1 ml plant-1—T1; prohexadione-Ca at 2 mg plant-1—T2; trinexapac-ethyl at 1 ml plant-1 plus prohexadione-Ca at 2 mg plant-1—T3; and Control—T4), five replications, and plots consisting of two plants. Two applications of a 300 ml plant-1 solution with the treatments were performed with a 30-day interval after the leaf emergence period (late September and October 2017). The trinexapac-ethyl and prohexadione-Ca plant growth regulators increased the grain yield of Jatropha curcas plants by increasing their vegetative growth, and number of inflorescences, and female and hermaphrodite flowers, but had no effect on the uniformity of fruit maturation. The treatment in which both plant growth regulators were used presented the best results, generating more vigorous and productive plants.

THE EFFECT OF FARMYARD , AND FOLIAR SPRAY WITH DRY YEAST , VITAMIN C ,AND ETHREL ON SQUASH ( Cucurbita pepoL. ) PLANTS.

Two field experiments were conducted during season of 2017and 2018growth seasons at Vegetable Private Farm of Shiba Distrect ,Zagazig Sharkia, Governorate, Egypt to study the effect of some treatments (control , Farmyard manure ,at 4m3/fad, dry yeast at 5 g/l, and vitamin C at200mg /l and ethrel concentrations ( 0 , 100 , 200 and 300ppm ) , and their interactions on plant growth (Cucurbita pepo cv. Zuccini), flowering traits , fruits yield and quality of squash plant. These treatments were laid out in split plot design arrangement with three replications. The treatments of organic manure, ascorbic acid were randomly distributed in main plots, while the ethrel concentration was randomly arranged in sub – plots .The summarized results obtained from this district study that, foliar spray of dry yeast at 5 g/l, being the most effective on vegetative growth characters , chemical composition of leaves, female flowers, fruit yield and quality of squash. Moreover, the concentration of 200 ppm ethrel, caused an increases in the all abovementioned characters of squash. In addition, the interaction between dry yeast at 5 g/l and 200 ppm ethrel came to the same trend in most of characters of squash plants Conclusively,obtained results indicate that foliar spray of dry yeast being the most effective on vegetative growth characters, chemical composition of leaves, number of female flowers, fruit yield and quality. Moreover, application ethrel at the concentration of 200 ppm caused an effective increase in all above mentioned parameters. In addition, the combination treatment between spraying dry yeast at the rate 5 g/l and ethrel at the concentration of 200 ppm came to the same effective trend in most studied characters of squash plants.

Ant pollination of Paepalanthus lundii (Eriocaulaceae) in Brazilian savanna.

Ant-plant associations are widely diverse and distributed throughout the world, leading to complex ecological networks. Regarding ant-plant mutualism, ant pollination is a very rare interaction and few studies have shown the role of ants as pollinators. Therefore, we aimed to evaluate the role of ants as effective pollinators of Paepalanthus lundii (Eriocaulaceae) in a Brazilian savanna. Fieldwork with experimental manipulation was conducted to evaluate the fitness of P. lundii, considering potential pollinators. For this, we mainly observed the number of seeds produced in different conditions: control, ant exclusion, exclusion of flying insects, and exclusion (entomophily test) of both ants and flying insects. Furthermore, we evaluated all floral visitors throughout the day, stigma receptivity, the numbers of male and female flowers, and patterns of species co-occurrence, which can indicate the presence of different pollinators in the plants at the same time. We observed a relation between seed production and ant visits; Camponotus crassus was the most frequent floral visitor and the most effective pollinator. Also, we observed a statistical difference between the numbers of male and female flowers produced, with a greater number of male flowers. Furthermore, P. lundii presented flowering asynchrony, with 12 different types of maturation sequence, which indicates a cross-pollination system. Lastly, we observed an overlap of the greatest abundance of C. crassus and the time of plant stigmatic receptivity, and a pattern of non co-occurrence of ants, which shows the pollinator role of this ant. Our data provide evidence that previous generalizations neglecting the importance of ants as pollinators are wrong. Brazilian savanna can reveal a lot about the ant-pollination syndrome, since this environment presents peculiar characteristics related to this association. Thus, this study has great significance for the understanding of the ant-pollination syndrome, and for the understanding of the complex ecological networks present in these dry arid systems.

Leafless Inflorescence Produces More Female Flowers and Fruit Yield Than Leafy Inflorescence in ‘Yu Her Pau’ Litchi

The purpose of this study was to determine whether the total number and percentage of female flowers and fruit yield were influenced by the type of inflorescence, i.e., leafless or leafy inflorescences in ‘Yu Her Pau’ litchi (Litchi chinensis Sonn.). Four 10-year-old field-grown plants in Chunghua, Taiwan, were assessed between March and June 2013. In total, 24 inflorescences comprising 12 each of leafless and leafy inflorescences were investigated. Leaves of the leafy inflorescence, defined as the fourth successive flush, attained maturity before female flower anthesis on 16 Mar. 2013. Shoot diameter and leaf number on the flowering (fruiting) shoot, total number of flowers, and total and percentage of female flowers were recorded. Fruit number, fruit set rate, cluster yield, and fruit quality were also determined at harvest between the two inflorescence types. The two inflorescence types had similar shoot diameters and total leaf number on a flowering shoot. The total number of flowers, female flowers, and the percentage female flowers in leafless inflorescences were 3741, 563, and 16.2%, respectively; these values were 1.3- to 1.7-fold higher (P ≤ 0.05) than those in leafy inflorescences, which were 2779, 326, and 12.2%, respectively. Leafless inflorescences had significantly higher fruit numbers and fruit yield per cluster at harvest (10.2 and 321.5 g, respectively), although there was no difference (P > 0.05) in fruit set rate between the two inflorescence types. No fruit quality trait, such as fruit, pericarp, aril, seed weight, aril proportion, and total soluble solid concentration of aril, was significant (P > 0.05) between the two inflorescence types. We concluded that leafless and leafy inflorescences of ‘Yu Her Pau’ had similar carbon assimilation supply potential; however, leafless inflorescence had greater performance in terms of female flower number and thus fruit yield, presumably due to the absence of assimilate competition brought by synchronous development of lateral inflorescence and immature leaves of panicle.

Protective role of selenium on cucumber (Cucumis sativus L.) exposed to cadmium and lead stress during reproductive stage role of selenium on heavy metals stress

The present study aimed to investigate the effect of selenium on flowering indices, sex determination of flowers, and yield of cucumber plant under heavy metal stress conditions. Treatments consisted of selenium (0, 4, 6, 8 mgL−1) and heavy metals of cadmium (0, 20, 25 µM) and lead (0, 60, 100 µM), which were applied in three stages during the experiment period. The results of this study showed that the stress of heavy metals with a negative effect on flowering indices resulted in delayed flowering and changing flower’s sex toward male flowers. Furthermore, delayed fruiting and significant decreases in fruit growth indices and total yield was observed in plants treated with cadmium and lead. Adding selenium to the culture medium resulted in accelerated flowering (reducing the time and number of nodes needed until the first flower emerges), the emergence of more male flowers, increased the ratio of the number of female flowers to male flowers in plants under stress, and the highest effect of this element was observed at the concentration 6 mg/L. Based on this results, the application of 4and 6mg/L selenium in stress and non-stress conditions enhanced fruiting (a significant reduction in the time required from cultivation to fertilize the first flower and the formation of fruit in lower nodes) and significantly increased the number of fruits, fruit length and diameter, single fruit weight and total yield, and the greatest effect of this element was observed in 6 mg/L concentration. The results of this study showed that selenium has a positive effect on control of stress conditions and improvement of flowering indices and total yield in cucumber plant under the stress of heavy elements of lead and cadmium.

Effect of organic nutrient management on growth and flowering of muskmelon (Cucumis melo L) cv GMM3

The experiment was carried out to study the effect of organic nutrient management on growth and flowering of muskmelon (Cucumis melo L) cv GMM 3 during summer 2017 at College of Horticulture (SDAU), Jagudan, Gujarat. Nine levels of organic nutrients were tested in the randomized block design with three replications. Treatments were evaluated on the basis of growth and flowering characteristics of muskmelon. Application of organic nutrients significantly affected growth and flowering parameters. Maximum vine length at 30 and 60 DAS, number of branches per plant, leaf area at 45 DAS, days taken to flower initiation, number of male and female flowers per plant, sex ratio and per cent fruit set were recorded with treatment 50 per cent N from FYM + 50 per cent N from poultry manure + biofertilizer [Azospirillium + phosphorus solubilizing bacteria (PSB) + KSM] + Trichoderma viride + neem oil.

Studies on performance of certain indigenous and exotic coconut genotypes [Cocos nucifera L.

A performance evaluation study was undertaken with 14 coconut genotypes which include eleven tall and three dwarf genotypes. Among the 14 coconut genotypes, eight exotic and six indigenous were from diverse geographical origins. All the coconut genotypes showed variation for yield, yield contributing characters and quality traits. East Coast Tall recorded maximum plant height while Laccadive Ordinary recorded maximum stem girth. With respect to leaf characters, Philippines Ordinary recorded maximum number of leaves while Jamaica Tall recorded maximum petiole length followed by Fiji Tall. With respect to the flowering traits, Philippines Ordinary recorded the maximum number of inflorescence per palm. The tall genotype, Laccadive micro recorded maximum number of female flowers. Length of stalk was highest in tall genotype Strait Settlement Green. Exotic tall genotype, Jamaica Tall recorded maximum spadix length. For the yield characters, Laccadive Ordinary recorded the highest number of bunch per palm per year by followed by Jamaica tall while Laccadive Micro recorded maximum number of nuts per bunch, number of nut per palm followed by Andaman Ordinary. For the nut characters studied, the exotic tall coconut genotype Jamaica Tall recorded maximum whole nut weight, dehusked nut weight, husk weight, husk thickness, kernel weight, shell weight, shell thickness followed by Laccadive Ordinary and Philippines Ordinary. On the other hand, Laccadive Ordinary recorded maximum kernel thickness and nut length. Andaman Ordinary recorded maximum nut breadth followed by Philippines Ordinary. With respect to quality traits, the indigenous tall genotypes Andaman Ordinary recorded maximum copra content and in case of oil content Laccadive Ordinary recorded maximum followed by Andaman Ordinary.

EFFECT FOLIAR SPRAYING OF ASCORBIC ACID ON FLOWERING GROWTH AND YIELD CHARACTERISTICS OF TWO VARIETIES OF (Cucurbita pepo. L) UNDER PLASTIC HOUSE

نفذت التجربة في أحد البيوت البلاستيكية العائدة لمحطة أبحاث قسم البستنة وهندسة الحدائق/ كلية الزراعة/ جامعة ديالى خلال الموسم الزراعي 2017- 2018. لدراسة تأثير الرش بحامض الأسكوربيك في الصفات الزهرية والحاصل ومكوناته لهجينين من قرع الكوسة V1 Carisma F1 والصنف الثاني F2 V2 Alexandria. تحت ظروف البيوت البلاستيكية، وبثلاث تراكيز (S3, S2, S1) (0 , 50، 100 ملغم/ لتر). تضمنت التجربة 6 معاملات، واستخدم تصميم القطاعات العشوائية الكاملة RCBD في تنفيذ التجربة وبثلاث مكررات ليصبح عدد الوحدات التجريبية 18 وحدة ضمت الوحدة التجريبية على 10 نباتات. أظهرت النتائج تفوق الهجين V2 في الصفات الزهرية (عدد الأزهار الذكرية والأنثوية والنسبة الجنسية ونسبة العقد) بلغت (26.10 زهرة. نبات- 1، 24.94 زهرة. نبات- 1، 1.04 و67.00)، كذلك تفوقه في معظم صفات الحاصل ومكوناته وهي عدد الثمار وحاصل النبات الواحد والحاصل الكلي إذ سجلت (8.63 ثمرة. نبات- 1، 1.733 كغم. نبات- 1، 2.911 طن. بيت- 1) على التوالي, بينما أدى الرش بحامض الأسكوربيك معاملة) S3تركيز 100 ملغم/ لتر) وكذلك التداخل الثنائي معاملة V2S3 (الرش بتركيز 100 ملغم/ لتر والهجين الثاني) إلى إعطاء أفضل النتائج في جميع الصفات الزهرية وصفات الحاصل ومكوناته متفوقه بذلك على جميع المعاملات التي تفوقت بدورها على معاملة المقارنة حيث سجلت الأخيرة أقل معدل لهذه الصفات.

APPLICATION RESULTS OF CUCUMBER GRAFTING ON DIFFERENT ROOTSTOSKS OF PUMPKIN

At present it is very actual in vegetable growing the development of highly effective and ecologically safe methods for increasing yields and plant resistance to unfavorable growth conditions. One of these methods is grafting. The goal of the study was to learn the influence of the rootstock on the characteristics of the growth, development and yield of cucumber. Research was conducted in 2015-2016 in greenhouse in spring-summer period in Armenia. As a scions was used cucumber variety Nazrvan, which was grafted on 5 pumpkin rootstocks (VI033637, VI03338, VI03364, VI040903, VI056328) from the collection of the World Vegetable Center (WVC). The grafting was carried out according to the standard method. When the VI033637 rootstock was used, flowering started 5 days earlier than the ungrafted plants, while when grafted on VI040903, the fruits ripened 6.2 days earlier. High increase of early yield (33.3%) received when used both above mentioned rootstocks. VI033638 – 4.1 kg/m2 and VI033664- 9.9 kg/m2 samples provided high increase of the total yield. For all the types of rootstocks the grafted plants of cucumber surpass the non-grafted ones by height from 4.7 % to 21.7%, by marketability of fruits from 5% to 14% and by fruit mass from 15 gr to 45 g. At the beginning of fruit-setting of cucumber plants the number of female flowers increased from 27% to 63% depending on the rootstock sample. The amount of dry substances in all grafted plants has increased by 4.4-8.8% and the amount of vitamin C by 1.8-9.2%. As a result of research carried out by us, perspective rootstocks (VIO33638 and VIO33664) are identified by a set of economically valuable characteristics which are recommended for applying in the further investigation and breeding activities and in production of grafted plants.

Effect of Paclobutrazol and NAA on Sex determination and Seed Yield of Medicinal Pumpkin (Cucurbıta pepo L.)

In order to evaluate the effect of plant growth regulators on sex determination and yield, an experiment was conducted by spraying different hormonal combinations on medicinal pumpkin. Experimental treatments were included different concentrations of NAA (25, 75, 100, 125 mg/l), paclobutrazol (50, 100, 200 and 300 mg/l) and combination of growth regulators (NAA 25 mg/l + PBZ 50 mg/l), (NAA 75 mg/l + PBZ 100 mg/l), (NAA 100 mg/l + PBZ 200 mg/l), (NAA 125 mg/l + PBZ 300 mg/l), and control (no application of growth regulators). Growth regulators were applied on the plants by spraying at the –two-leaf and four-leaf stages. Results showed that spraying paclobutrazol and NAA caused increase in number of female flowers, fruits per plant, seeds per fruits, 1000 seed weight and seed yield per hectare, but the number of male flowers and ratio of male to female flowers were decreased compared to their values in control plants. The highest fresh and dried seed yield of pumpkin seed was obtained with 50 mg/l paclobutrazol.

Flowering and fruiting seasonal changes of six accessions of Jatropha curcas L. in a semi-arid region of Senegal

Jatropha curcas is the priority species for biofuel promotion in Senegal. However the lack of knowledge on floral biology and fruiting of this plant remains a problem to increase its yield and improve farmers’ adoption. The objectives of this study were to assess seasonal changes on flowering and fruiting of six accessions of Jatropha curcas in semi-arid area, Senegal. In this study the total number of inflorescences, flowers and fruits were evaluated during six month son four years old plants, installed in the Agricultural Engineering School ( ENSA) of Thies. The results showed significant effect of the studied factors (season, accession) and interaction between them on floral and fruiting traits of J. curcas. Due to more favorable climatic conditions, the performance of flowering is better in the wet season. During this season, the number of male and female flowers ranged, respectively from 107.47–191.60 and from 2.47–11.87 per inflorescence. Consequently, ripe fruits production was higher in wet season and varied between66 and 97% of the total production. Two peaks of flowering were observed; the first one occurred in dry season (April, 24th- June 6th) and the second, with the highest number of inflorescences, arrived in wet season (8 - 22 July). Fruiting patterns is highest concentration between at the end of the wet season (September 15th and October 3rd).High seed yields were observed with the accessions CE6 (2739.3 kg ha-1), CE97 (1451.0 kg ha-1) and CE95 (1326.3 kg ha-1) that are promising for biofuel production in semi-arid areas of Senegal.

Análisis fenológico comparativo de las accesiones más productivas de un banco de germoplasma de Jatropha curcas (tempate), en Costa Rica

La especie Jatropha curcas (tempate) es típica de la zona mesoamericana, su centro de origen se ha establecido en México. Ha sido domesticada para uso en cercas vivas y por su valor medicinal según el conocimiento tradicional. En la actualidad se cataloga como una especie de alto valor para la producción de aceites que pueden tener uso en biocombustibles o como diluyente de pinturas. En Costa Rica se ha establecido un banco de germoplasma en la estación experimental Fabio Baudrit de la Universidad de Costa Rica, ubicada en la Garita de Alajuela. Comprende un total de 52 accesiones procedentes de todo el país y algunas de ellas de origen internacional. Producto del seguimiento anual del mismo se tuvo conocimiento de que las procedencias Turrubares JCCR36 ,Jacó JCCR-3 ,El Barro de Turrubares JCCR-43,Orotina JCCR-1, Marichal JCCR-42, Tempate 1 JCCR-6, San Vito 2 JCCR-30, México 2 JCCR-31,India JCCR-27, Tempate 1-Guanacaste JCCR-23, fueron las más productivas y de cada una se seleccionaron 3 individuos a los que se les dio un seguimiento semanal estimando el número de flores femeninas, masculinas, número de inflorescencias, número de frutos. A los datos se les aplicó un análisis no paramétrico de Kruskal Wallis y los resultados se correlacionaron con el nivel de irradiación y precipitación. Lo que permitió estimar que las procedencias más productivas fueron San Vito 2 JCCR-30, México 2 JCCR-31 y Tempate 1-Guanacaste-23. La mayor tasa de irradiancia se registró en los meses de febrero- marzo en el 2014 y marzo-abril en el 2015, se encontró correlaciones inversas mayores a 0,40 entre la radiación solar para los años 2014 y 2015, con respecto a la producción de flores, mientras que el comportamiento de la producción de inflorescencias presentó correlaciones con la precipitación y la radiación solar.