Poor Flowering Research Articles

Effect of Irrigation Intervals and Plastic Mulching On Flower Production of Carnation

Calyx splitting is a physiological disorder that results in poor flower production and vase life in carnation. Several scientific reports and literature suggests that this physiological die back and curly tip of carnation flowers might be due to the water stress and potassium deficiency. Keeping in view these facts a field experiment was carried out to study the effect of irrigation intervals and plastic mulching on flower production and control of calyx split in carnation at Ornamental Horticulture Nursery, The University of Agriculture Peshawar, in 2020. Randomized Complete Block Design with a split plot arrangement having two factors was used. Treatments were repeated three times. The plants of carnation were irrigated at different interval (3, 6, 9 and 12 days) allotted to main plots and plastic mulches (transparent, black and green and control / no mulching) were assigned to subplots. Data pertaining to irrigation intervals revealed that least days to flowering (89.7), least calyx splitting (6.1%) and maximum vase life (11.33 days) were recorded in plants irrigated with 12 days’ interval that were statistically similar to the effect of irrigation at 9 days of interval. Findings regarding plastic mulches showed that maximum chlorophyll content (62.8 SPAD), days to flowering (100.5), dry flower weight (2.4g) and vase life (10.95 days) with minimum calyx splitting (7.4%) were recorded in carnation plants of plots covered with green plastic mulch that were statistically similar to the effect of black and transparent plastic mulches. It is concluded that irrigation intervals of 9 and 12 days resulted in early flowering, least calyx splitting and extended vase life. While use of plastic (Transparent, black or green) as mulching material proved superior as compared to control/ no mulching.

Prediction of Inflorescence Emergence in ‘Yu Her Pau’ Litchi Under Climate Change Using an Optimised Model

ABSTRACTFor litchi (Litchi chinensis), successful floral induction requires adequate cool temperatures in winter, perceived by mature leaves like many other subtropical fruit species. As a result, rising ambient temperatures due to global climate change has posed a threat to litchi flowering and fruit production. The goal of this research was to assess the potential impacts of climate change on flowering in ‘Yu Her Pau’ litchi on Taiwan. To better characterise the relationship between temperatures and inflorescence emergence (IE), we built a model by applying the beta‐distribution function method with 12 phenological datasets (two orchard blocks for 6 years) recorded from field‐grown ‘Yu Her Pau’ litchi trees. For this predictive model, the minimum, maximum, and optimal temperatures that resulted in successful floral induction were estimated to be 0.0°C, 21.9°C, and 19.8°C, respectively; under these criteria, at least 60.37 units of cumulative cool temperatures are necessary for IE based on the historical data. Subsequently, the IE model was used to evaluate the likelihood of successful flowering in ‘Yu Her Pau’ litchi at four major producing areas on Taiwan during five decades from 2026 to 2075, respectively, under three separate climate change (emission) scenarios based on three General Circulation Models (GCMs) in. Our results, based on any of the GCMs, suggested that ‘Yu Her Pau’ litchi grown on Southern Taiwan could face poor flowering due to insufficient cool winter temperatures in the coming decade even in the emission scenario with very stringent mitigation effort, which can lead to serious crop loss in the near future.

Influence of post-vegetative foliar application of nitrogen and selenium on micrometeorological parameters, phenology, and yield of wheat (Triticum aestivum L.)

Excessive and continuous use of commercial-grade fertilizers in large quantities during the post-Green Revolution era has led to significant environmental impacts, besides escalating the cost of production in staple crops. Such over-reliance on chemical fertilizers in intensive agriculture and a limited focus on balanced nutrient management have led to an increase in micronutrient deficiency in the sub-tropical part of India. This micronutrient deficiency leads to stunted growth, poor flowering, and reduced grain and fruit formation, directly impacting overall crop productivity. Hence, the introduction of nano form of fertilizers and integration of them with bulk/commercial form will help in improving the nutrient use efficiency, reduce production costs vis-a-vis enhancement in the plant growth, and yield more effectively than the traditional fertilizers. Proper nutrient management promotes healthy development at each stage, from seedling establishment to maturation and ripening, ensuring optimal yields and quality. Hence, fertilization directly and profoundly impacts the phonological stages of the crops. In this respect, a field experiment was conducted at Ludhiana and Fatehgarh Sahib, Punjab, India, during the rabi season of 2021-22. The experiment was laid out in a Randomized Completely Block Design (RCBD) with four replications and 11 treatments. Besides an absolute control where no fertilizer was applied (T1), ten other treatments were commonly fertilized with the recommended dose of fertilizers (RDF), i.e., 125 kg N and 62.5 kg P2O5 ha-1). The treatment varied in applying bulk and nano N (6% urea) and Se (15 ppm) at reproductive phases. The normalized difference vegetation index (NDVI) score and chlorophyll index improved with foliar spray of both bulk and nano urea forms alone or in combination with Se (bulk or nano). The effect of foliar sprays of urea and selenium, either in bulk or nano form, alone or in combination, was insignificant. The reproductive stages, viz. heading, grain filling, and physiological maturity, are prolonged with late season spray of 6% bulk or nano urea alone or in addition to bulk or nano selenium. Maximum days to grain filling was in a foliar spray of nano urea 6% along with nano selenium 15 ppm, further leading to higher grain and biological yield.

Loss of daylength sensitivity by splice site mutation in Cannabis pseudo-response regulator.

Photoperiod insensitivity (auto-flowering) in drug-type Cannabis sativa circumvents the need for short day (SD) flowering requirements making outdoor cultivation in high latitudes possible. However, the benefits of photoperiod insensitivity are counterbalanced by low cannabinoid content and poor flower quality in auto-flowering genotypes. Despite recent studies in cannabis flowering, a mechanistic understanding of photoperiod insensitivity is still lacking. We used a combination of genome-wide association study and genetic fine-mapping to identify the genetic cause of auto-flowering in cannabis. We then used gene expression analyses and transient transformation assays to characterize flowering time control. Herein, we identify a splice site mutation within circadian clock gene PSEUDO-RESPONSE REGULATOR 37 (CsPRR37) in auto-flowering cannabis. We show that CsPRR37 represses FT expression and its circadian oscillations transition to a less repressive state during SD as compared to long days (LD). We identify several key circadian clock genes whose expression is altered in auto-flowering cannabis, particularly under non-inductive LD. Research into the pervasiveness of this mutation and others affecting flowering time will help elucidate cannabis domestication history and advance cannabis breeding toward a more sustainable outdoor cultivation system.

Design and synthesis of novel N, N′-substituted benzamide derivatives as potential insecticidal agents against the white mango scale insect, Aulacaspis tubercularis (Hemiptera: Diaspididae)

The white mango scale insect Aulacaspis tubercularis (Newstead) (Hemiptera: Diaspididae), which causes defoliation, drying out of young twigs, dieback, poor flowering, and decreased fruit output, causes serious damage to mango trees in Egypt. Attacks on mango fruits result in pink imperfections that lower their value as a commercial and export item. The current report aims to support the development of integrated management plans to combat A. tuberculosis and to identify more effective, eco-friendly insecticides. The bug may cause a considerable decrease in mango production and jeopardize the sustainability of mango plantation production if no management measures are taken. Currently, the application of a small number of insecticides—the majority of which have poor performance and are disruptive is the primary method used to manage A. tubercularis. In order to suppress this insect, we created novel pesticides called insect growth regulators (N, N′-substituted benzamide derivatives). By using both traditional and elemental spectroscopic investigations (IR, 1HNMR, and 13CNMR), these synthesized compounds which are linked to the most well-known insect growth regulator insecticides had their structures validated. The findings showed that A. tubercularis nymphs were more responsive to the evaluated treatments than adult females. After one day of application, all tested treatments resulted in a sizable proportion of mortality; the percentage of mortality increased with time for both A. tubercularis nymphs and adult females. Furthermore, the treatment with compound 3b was more effective than other synthesized compounds, with a LC50 of 0.318 ppm against nymphs and a LC50 of 0.993 ppm against adult females of A. tubercularis. While the treatment with compound 5 was the least toxic for controlling this pest, many assessments are essential to studying the efficacy of these treatments on advantageous insects.

Deficient Irrigation and Its Impact on Water Use Efficiency, Maize Yield and some of Its Components

In spring 2021, a clay mixture soil field experiment was conducted in one of Babylon province’s Al-Ataij agricultural fields, 2 km from Hilla’s centre (32°29"24.178″N 43°26"56.459″E) to study the effects of incomplete irrigation on crop sensitivity, water use efficiency, maize yield, and some of its components. Three-replicate RCBDs. Eight treatments were used: the full irrigation treatment (control) after 50% of the available water was drained, and seven incomplete irrigation treatments (25% of the available water was provided after the soil moisture content reached the permanent wilting point) within the root zone. Negative or incomplete irrigation during vegetative development, blossoming, crop output, or both. The number of grains, 1000-grain weight, total yield, crop and field irrigation efficiency, additional water, and real water consumption were calculated. All farming followed rules. Water balance equations calculated effective evapotranspiration (Eta). Full irrigation used 335.26 mm, partial irrigation 341.55 mm, and 147.10 mm. Partial irrigation only lowered real water use by 9.61% in crop formation, 12.90% in vegetative development, and 26.11% in blooming. Insufficient irrigation did not alter yield components, number of grains, 1000-grain weight, or grain yield during yield development. Irrigation decreased characteristics by 1.2, 1.7, and 5.0%. Incomplete vegetative and flowering watering elevated attribute drop rates to 28.2, 9.4, and 54.6. Incomplete watering affects blooming more than vegetative growth and production. Except during growth phases, incomplete irrigation during crop development outperformed all other incomplete and full irrigation treatments. Incomplete crop irrigation was most efficient (1.075 kg/grain 1) and least average (0.75) kg/grain. Water-tolerant crop growth. Water-sensitive plant growth. Correcting poor flower watering boosted crop irrigation efficiency. Partial irrigation only improved crop development ethically.

A Review on White Mango Scale Biology, Ecology, Distribution and Management

The white mango scale (WMS) insect, Aulacaspis tubercularis (Hemiptera: Diaspididae), is a polyphagous, multivoltine pest which is a serious threat to qualitative mango production and export. The WMS insect sucks sap from leaves, branches and fruits. The heavy infestation of this pest may cause the falling of young leaves, drying up of twigs, poor flowering, and, finally, reduce the quality of fruits by producing pink spots on fruits’ surface. This review paper was written to provide comprehensive information about pest biology, ecology and management in different parts of the world. WMS was first reported on the island of Formosa on Mangifera indica in 1929 and later on in the Caribbean Islands, India and Brazil. Now it is found in almost 69 mango-producing countries of the world. The thermal regime may affect the population of pests. In Australia, the life cycle is completed in 35–40 days in summer and 70–85 days in winter. Variety, age of plants, number of trees per acre, canopy size and sunlight penetration affect the density of WMS. Different Coccinellid beetles and parasitoid Encarsia femorosa feed on WMS; however, farmers most commonly use insecticides to get rid of this pest. In Pakistan, WMS is a growing threat to the export of mangoes; hence IPM plan is needed to reduce the pest numbers and enhance qualitative mango production.

B. Shaw’s play «Pygmalion» in the perspective of interdiscursivity

In the article, discourse of B. Shaws play Pygmalion is studied from the standpoint of view of interdiscursivity theory with the use of methods of critical, linguopragmatic and sociolinguistic analyses. The authors definition of the term interdiscursivity is given. Within the analyzed book, a number of discourses are singled out. Among them are mundane linguistic, philosophical and pedagogical discourses. It is pointed out that in the light of their mundane, non-institutional character, these discursive spheres have not been studied in detail even though the scientific interest to mundane discourses is growing. These considerations determine the importance of the undertaken research. The main discourse of B. Shaws paly Pygmalion is recognized to be mundane pedagogical one. However, the latter is determined by the hero of the play Higginss mundane philosophy who takes on the role of the teacher. His pupil is Eliza Doolittle, a poor flower girl, who speaks a dialect of the English language, viz. cockney. In the process of research, it is found out that if mundane pedagogical discourse is understood broadly, it can include the sayings of other characters of the book Higginss friend Pickering, Higginss mother, etc. The most important linguopragmatic opposition of mundane pedagogical discourse is recognized to be politeness impoliteness which is expressed communicatively as the result of uneven distribution of power between the teacher and the pupil which in the course of everyday mundane interaction may be significantly reviewed, for example be reversed in the pupils favor. The lack of institutional limitations enriches the speech genre specificity of the studied discourse which is hybrid in its essence, i.e., located at the intersection of different discursive practices.

Source-Sink Alterations in Rice Fallow Adaptive Blackgram Variety ADT3 for Enhancement of Yield and Quality of Seed

Seed Production of rice fallow blackgram variety, ADT3 has limitations due to inherent issues of soil fertility, climate change and thermo sensitivity results in poor flowering, reduced pod setting and poor seed filling. Macro and micro nutrients application during critical stages of growth were tried to improve the seed yield and quality in rice fallow blackgram variety ADT3. The combined foliar spraying of 0.5% NPK (macro) and 0.2% chelated micro nutrients mixture (Fe 2.5%, Mn 1.0%, Zn 3.0%, Cu 1.0%, Mo 0.1% and B 0.5%), were sprayed on 15th (Vegetative phase), 30th (Reproductive phase), 45th ( Flowering and pod formation phase) days after germination improved the growth and seed parameters viz., plant height, number of branches, number of pods per plant, number of seeds per pod, filled seed % which resulted in increased seed yield in rice fallow blackgram variety, ADT3.
 Response of macro and micro nutrients through foliar mode revealed the lack of soil fertility resulting in poor uptake of macro and micro nutrients. Foliar application induced uniform flowering and synchronous maturity of pods with least shattering which would facilitate mechanical harvesting. Foliar application of macro and micro nutrients phenotypically altered the source-sink which greatly influenced the yield of seed, germination and seedling quality parameters.

Effect of Micronutrients (Boron & Zinc) on Growth, Flowering and Quality of Carnation (Dianthus caryophyllus L.) Under Naturally Ventilated Polyhouse Conditions of Prayagraj, India

The present investigation was done to study the effect of micronutrients (Boron & Zinc) on growth, flowering and quality of carnation (Dianthus caryophyllus L.) under naturally ventilated polyhouse conditions of Prayagraj. The experiment was conducted in Randomized Block Design (RBD) with fifteen treatments replicated thrice. Foliar application with three levels of boron (0.05%, 0.1% and 0.15%), three levels of zinc (0.2%, 0.4%, and 0.6%) and treatment combinations of both boron and zinc along with control were applied. Among all the treatments, T2 (B @ 0.1%) recorded significantly taller plants (84.71 cm), more number of leaves (165.47), more number of shoots (7.53), more number of internodes (17.27), higher internodal length (5.21 cm), longer bud (3.63 cm), more bud diameter (2.33 cm), higher flower stalk girth (4.86 mm) and more vase life (11.2 days). However, treatment T6 (Zn @ 0.6 %) exhibited early days for bud initiation (124.27 days), bud opening (14.47 days), 50 percent flowering (138.73 days), more number of cut flower stalks per plant (7.13) and more number of flowers per meter square (178.33) while treatment T5 (Zn @ 0.4 %) exhibited longer flower stalk (66.23 cm) and treatment T10 (B @ 0.1 % + Zn @ 0.2 %) produced good flower diameter (6.62 cm). Poor flowers were generated by plants that were not given micronutrients. So, T2 (B @ 0.1 %) and T6 (Zn @ 0.6 %) can be applied topically to improve the quality of flowers. Hence, applications of micronutrient are proven to be crucial for improving the vegetative growth, flowering, quality and yield parameters of carnation grown under naturally ventilated polyhouse conditions of Prayagraj.

Conservation Strategy for Endangered Medicinal Plant - Black Turmeric (<i>Curcuma caesia</i>)

Black turmeric ( Curcuma caesia Roxb.) is commonly known as kali haldi and it belongs to the family Zingiberaceae. The plant has a characteristic rhizome flesh of bluish-black colour with pungent smell and hot bitter taste. The crop is gaining popularity in nowadays due to its anticancerous property and short supply from the traditional forest areas. It is widely used as an important medicine to cure cancer in Chinese medicine. Its availability in forest area has continuously declined and the species needs to be restoring in non-conventional forest areas especially on farmer's field. It is propagated through rhizomes and large quantity of rhizome is required because of its poor vegetative propagation efficiency. Rhizomes are susceptible to diseases that cause tissue senescence and degeneration during storage and cultivation. It is difficult to propagate through seed because of poor flowering and inability to seed set. The planting material is not chiefly available for commercial cultivation. To overcome this problem, planting material produced from single bud rhizome of black turmeric under shade net condition will be planted instead of rhizomes. The main objective of this paper is to standardize the growing media for mass multiplication of black turmeric. Among the various treatments, rhizome with single bud planted in a growing media of cocopeat + vermicompost + Pseudomonas flouorescence give better crop establishment (95.99 per cent). Hence, rapid multiplication of black turmeric through single bud rhizome has been considered as the conservation strategy for this endangered medicinal plant.

Genotypes by environment effect on flowering and seed set in cassava, Manihot esculenta Crantz in Uganda

Cassava (Manihot esculenta Crantz) production has been constrained by biotic and abiotic factors, which could be solved by conventional breeding. However, cassava hybridization is difficult because many genotypes do not flower or set seeds and yet cassava sexual reproduction is essential for breeding programs. Consequently, this study was undertaken to identify agro ecologies in Uganda that best promote cassava flowering and seed set in order to facilitate breeding. Field evaluation of eight genotypes in randomized complete block design with three replications at three agro-ecologies of Uganda for two cropping seasons was conducted. Weather data were monitored and cassava flowering/seed set-related traits were collected at one-month interval commencing from 1.5 Months after planting. Results indicated that varieties previously categorized as high flowering and seed set performed differently than those identified as poor flowering and seed set, although with varying genotypic differences in each environment. Genotypes mean performances, additive main effect and multiplicative interaction and genotype main effect and genotype by environment interaction bi-plots model’ results indicated Rwebitaba in Western savannah grassland agro-ecology and Namulonge-NaCRRI in Lake Victoria Crescent agro-ecology as the most favorable environments for the performance of all the evaluated traits, and season one as the most favorable season. However, the most stable environment for all the evaluated traits was Abi-ZARDI. Conclusively, the high proportion of variation which occurred between genotypes and environments was explained by the genotypic variances. Dry months had poorer cassava flower initiation and development than wet months of the cropping season. Therefore, Abi-ZARDI in North-western savannah grassland agro-ecology and season one could be recommended for the establishment and timing of cassava breeding nursery.

Strategies to combat the problem of yam anthracnose disease: Status and prospects

Yam (Dioscorea spp.) anthracnose, caused by Colletotrichum alatae, is the most devastating fungal disease of yam in West Africa, leading to 50%–90% of tuber yield losses in severe cases. In some instances, plants die without producing any tubers or each shoot may produce several small tubers before it dies if the disease strikes early. C. alatae affects all parts of the yam plant at all stages of development, including leaves, stems, tubers, and seeds of yams, and it is highly prevalent in the yam belt region and other yam‐producing countries in the world. Traditional methods adopted by farmers to control the disease have not been very successful. Fungicides have also failed to provide long‐lasting control. Although conventional breeding and genomics‐assisted breeding have been used to develop some level of resistance to anthracnose in Dioscorea alata, the appearance of new and more virulent strains makes the development of improved varieties with broad‐spectrum and durable resistance critical. These shortcomings, coupled with interspecific incompatibility, dioecy, polyploidy, poor flowering, and the long breeding cycle of the crop, have prompted researchers to explore biotechnological techniques to complement conventional breeding to speed up crop improvement. Modern biotechnological tools have the potential of producing fungus‐resistant cultivars, thereby bypassing the natural bottlenecks of traditional breeding. This article reviews the existing biotechnological strategies and proposes several approaches that could be adopted to develop anthracnose‐resistant yam varieties for improved food security in West Africa.

Effects of Mulching on Soil Properties and <i>Actinidia arguta</i> Fruit Yield in South Korea

Yield and fruit size are under the control of many interacting factors and crop failures can be caused by climatic extremes and poor flowering. Nevertheless, this study has shown that mulching, through the creation of improved soil properties and reduced environmental stress, has the potential to substantially increase A. arguta fruit size and yield. The mulched site performed better than the site without mulch in reducing soil temperature, increasing soil moisture and controlling available phosphorus. Moreover, mulching improved both yield and fruit size. In light of this, we hope that the results of our research will provide useful information for the cultivation of A. arguta in South Korea. However, it also seems necessary to conduct research on the use of different types of mulch and on the economic profitability of mulch in the future.

Spring Freeze Damage of Pecan Bloom: A Review

Pecan is native to the United States. The US is the world’s largest pecan producer with an average yearly production of 250 to 300 million pounds; 80 percent of the world’s supply. Georgia, New Mexico, Texas, Arizona, Oklahoma, California, Louisiana, and Florida are the major US pecan producing states. Pecan trees frequently suffer from spring freeze at bud break and bloom as the buds are quite sensitive to freeze damage. This leads to poor flower and nut production. This review focuses on the impact of spring freeze during bud differentiation and flower development. Spring freeze kills the primary terminal buds, the pecan tree has a second chance for growth and flowering through secondary buds. Unfortunately, secondary buds have less bloom potential than primary buds and nut yield is reduced. Spring freeze damage depends on severity of the freeze, bud growth stage, cultivar type and tree age, tree height and tree vigor. This review discusses the impact of temperature on structure and function of male and female reproductive organs. It also summarizes carbohydrate relations as another factor that may play an important role in spring growth and transition of primary and secondary buds to flowers.

Role of water percolation in reproductive physiology of hazelnut (Corylus spp.)

Hazelnut (Corylus spp.) flowering occurs during late winters and early spring which coincides with erratic fluctuating weather patterns. Irregular and reduced precipitation, especially in the form of snow, is assumed to dictate poor flowering and enhanced injury to catkins, especially in the sourced cultivars of interest to growers. We investigated the effect of water (precipitation received as rain and or snow) percolation during snowmelt period using phenological endpoints such as female flower ratio, bud position of female flower occurrence, and catkin dehiscence in sourced and locally adapted cultivars. These reproductive events were also analyzed for biochemical endpoints such as the concentrations of tryptophan, serotonin and melatonin in temporally collected bud or catkin samples. In addition, the yield responses of the tagged twigs were tracked and analyzed. When snow was consistently removed from the root zone (NS) or when a prior placed plastic sheet (P) disallowed water percolation, the percentage of female flowers and apical dominance declined in the sourced cultivars suggesting an erratic gradient between aerial and belowground temperature. The presence of snow cover resulted in increased probability of female flowers from dormant buds in sourced cultivars. Tryptophan was found to accumulate in the dormant buds of sourced cultivars where snow was not disturbed, while serotonin concentrations were significantly higher in NS and P treatments. Melatonin concentrations were notably high in dormant flower and vegetative buds of locally adapted cultivars especially subjected to P treatment. The biochemical markers may not only assist in identifying cold tolerance but also reveal abiotic stress negating responses modulated by relative concentrations of these molecules. Our results demonstrate that ideal conditions of good precipitation, especially as snow, would not only blanket to provide thermoregulation but also maintain the sensitive gradient on which temperate trees rely to break dormancy and initiate flower development. These findings also suggest that the use of horticultural alternatives such as thermal mulch could be an option for mitigating adverse conditions of reduced water percolation which affect reproductive physiology of hazelnut.

Advancement and efficacy of plant growth regulators in Ber (Ziziphus mauritiana Lamk) - A review

Ber (Ziziphus maurtiana) is an important minor fruit crop of India. Over the years the crop is now widely domesticated and commercial orchards of Ber are now available. With wide commercialization, many physiological problems, i.e. flowers and fruit drop, embryo abortion, poor flowering and fruit setting, abnormal and small size fruits etc. were observed which cause huge loss to the growers. In order to minimize these problems, over the years many experiments and advancement have been done, and among them, usage of plant growth regulators is one of the most adopted methods and is utilized to improve flowering fruiting and yield with improved fruit quality. The current review discusses the role of different plant growth regulators and how they influence each fruit character. This information could be useful to the researchers in planning further advance research in this aspect and for the commercial growers to decide the proper treatments to mitigate the problems.

Sulphur on Groundnut Yield and Quality

Groundnut yield is enhanced by the sulfur supplement which aids in the improvement of chlorophyll synthesis leading to higher partitioning of assimilates resulting in high growth and yield parameters. Sulfur deficiency results in poor flowering, fruiting, cupping of leaves, reddening of stems, petiole and stunted growth. Sulfur is required for the synthesis of protein, oils and vitamins. Methionine (21 % S), cysteine (26 % S), Cystine (27 % S) are important amino-acids that are supplied by sulfur triggers protein synthesis and biochemical reactions that increases oil content and oil quality .Variety of sulfur sources and levels had been tried in experiments by researchers to evaluate the potential level that sustains high growth, yield and productivity of groundnut resulting in higher net returns. Application of sulfur about 40-60 kg ha-1 proved to an optimistic level through gypsum sources for groundnut.

Phenological diversity of flowering and fruiting in cassava germplasm

Genetic and environmental factors can influence the flowering and fruit setting performance of cassava varieties. The objective of this work was to assess the genetic variability of cassava germplasm for flowering and fruiting traits, as well as to cluster the genotypes based on based on its flowering performance. A total of 1032 accessions were evaluated monthly from 3 to 12 months after planting – MAP for flower and fruit production using a grade scale ranging from 0 absence or poor flowering to 3 full flowering, and the accumulated degree-days ADD was recorded for each period. The following traits were analyzed: a the mean flowering score MFS from 3 to 12 MAP and b a weighted average of the flowering scores that emphasizes early flowering WAS. The cassava accessions were clustered based on principal component analysis PCA. Seven clusters were identified via PCA, with very contrasting traits including a early flowering 8.5 % of the accessions, Group 4); b) consistent flowering after 2036 ADD (0.6 % of the accessions, Group 2); and c) accessions that do not flower (54 % of the accessions, Group 7). For most of the cassava germplasm, flowering occurred during the longest photoperiod (5–6 MAP). This study demonstrated that accessions belonging to Group 2 are very interesting for breeding programs and genomic studies due to their high flowering throughout the year. This is the first report of phenological diversity of flowering and fruiting performance in cassava germplasm.

Factors of yield determination in faba bean (Vicia faba)

Faba bean (Vicia faba L.) is an important cool-season legume crop that ranks fourth after chickpea (Cicer arietinum L.), field pea (Pisum sativum L.) and lentil (Lens culinaris L.) in terms of total production. The global production of faba bean was 4.8 Mt in 2017, with China, Ethiopia and Australia being the largest producers (1.8, 0.93 and 0.37 Mt, respectively). However, its area of production is not increasing relative to other crops, mainly because of high yield instability. This can be attributed to several factors related to plant traits (e.g. phenology, morpho-physiology) and biotic and abiotic stresses. Faba bean has a very poor flower:pod ratio, with a maximum 20% of flowers resulting in pods. Environmental stresses such as frost, heat and drought cause significant damage to flowers and young pods; therefore, matching phenology of crops to the environment is important for avoiding or minimising detrimental effects of unfavourable environmental conditions. In order to improve adaptation and yield, we need to understand the main factors affecting plant growth, including biotic stresses, identify the main yield components, and find traits associated with tolerance to frost, heat and drought.