Late-season Plant Research Articles

Tracking Sweet Potato Leaf Curl Virus through Field Production: Implications for Sustainable Sweetpotato Production and Breeding Practices.

Sweet potato leaf curl virus (SPLCV) is a whitefly-transmitted begomovirus infecting sweetpotato and other morning glory (Convolvulaceae) species worldwide. The virus is widespread at the USDA, ARS, U.S. Vegetable Laboratory (USVL), and testing of germplasm maintained in the breeding program indicates nearly 100% infection in storage roots of materials propagated for at least four years. Prior to the public release of new germplasm, viruses must be eliminated via laborious and time-consuming meristem-tip culture. The identification of virus-free seedlings early in the selection process can offer an alternative to meristem-tip culture. In this study, we investigated the transmission of SPLCV over two years of consecutive field plantings (early and late) of sweetpotato. While SPLCV is endemic at the USVL, virus transmission pressure over the typical cultivation season is unknown, and avoidance of virus transmission paired with the selection and maintenance of clean material may be a viable alternative to virus elimination. In 2022, the storage roots of 39 first-year seedling (FYS) selections were tested for SPLCV after early-season cultivation, revealing a single selection (2.6%) with a positive test. Similar testing was conducted in 2023 with no SPLCV-positive FYS selections detected. To further assess SPLCV acquisition in the field, replicated late-season plantings of each selected FYS (n = 37) were monitored from planting to harvest. Testing was conducted at 60 and 120 days after planting (DAP). Approximately 35% of the bulk samples were infected at 60 DAP, and infection increased to 52.3% by 120 DAP. Testing of individuals within selected positive bulked samples did not support 100% infection at harvest. Altogether, these results demonstrate that SPLCV transmission during early planting is sufficiently low to facilitate the maintenance of virus-free selections, offering an alternative to virus cleaning and a cultivation strategy that may be leveraged for production.

Effects of Conservation Tillage Method, Phosphorus Level, and Variety on Soil Organic Carbon and Cowpea Performance at Minna in Nigeria’s Southern Guinea Savanna

The study was carried out at the Teaching and Research Farm of the Federal University of Technology Minna, Gidan Kwano Campus in Latitude 9° 41' N, Longitude 6° 31' E, and Altitude 258.5 m above sea level. This study was conducted across 2 seasons within the cropping season of 2017 to determine the effects of tillage method, phosphorus level, and cowpea variety on soil organic carbon and cowpea performance in Minna. The experiment was therefore a 3x3x3 factorial arrangement in a split-plot design with tillage methods (zero, reduced, and manual ridging) and cowpea varieties (IT93K-452-1, IT99K-573-1-1, and IT90K-277-2) forming the main plot while phosphorus levels (0 P kg ha-1, 30 P kg ha-1, and 60 P kg ha-1) formed the sub-plot with 3 replicates. Results obtained revealed that soil organic carbon was not significantly affected by tillage method and phosphorus level alone, regardless of the planting season. Cowpea variety alone significantly affected organic carbon only in the late planting season. Zero tillage, 60 kg P ha-1, and IT93K-452-1 produced the highest soil organic carbon content, respectively. In the early season, N fixed was highest (0.98 g plant-1) when cowpea was fertilized with 60 Kg P ha-1 under zero tillage. The closest to this value (0.92 g plant-1) was recorded in the late season when 60 kg P ha-1 was supplied to cowpea under manual tillage. Regardless of the planting season and varietal difference, cowpea recorded the highest N fixed when fertilized with 60 kg P ha-1. Across varieties, cowpea fixed more N under zero tillage than the other tillage methods, especially in the early season. In the late season, only IT90K-277-2 fixed N (0.49 g plant-1) under zero tillage that was statistically not different from the highest N fixed due to manual tillage of soil under the cultivation of IT93K-452-1 and IT99K-573-1-1 (0.62 g plant-1, respectively). In the early season, IT99K-573-1-1 cultivated under zero tillage produced the highest grain yield (404.11 kg ha-1). Fodder yield followed a different trend compared to grain yield. In the early planting season, cowpea fertilized with 60 kg P ha-1 produced the highest fodder yield, while in the late season, the application of 30 kg P ha-1 produced the highest fodder yield. Regardless of the planting season, grain yield was highest when IT99K-573-1-1 was fertilized with 60 kg P ha-1. Averagely, soil organic carbon content, N fixed, and grain yield values were highest during the late planting than the early planting season. The reverse was, however, the case for fodder yield, seedling emergence, root length, root, and shoot biomass, respectively. For the best performance in cowpea production, farmers are encouraged to plant IT99K-573-1-1 on zero-tilled soil with phosphorus application at the rate of 60 kg ha-1. IT90K-277-2, which is the most genetically stable variety across seasons, will be most ideal in controlling negative climate change and should therefore be considered for further investigations.

Production and disease status of three climbing beans varieties in the monomodal humid forest of Cameroon

The availability of beans at a relatively cheaper price compared to meat and other protein sources cater for the protein requirements of people with low purchasing power. This study was carried out on three climbing beans varieties PNN, DOR 701 and MCX to evaluate growth, yield and disease prevalence across two growing seasons. The design of the experiment was complete randomized block design with the three replicates, 15 plants were randomly selected and tagged from each variety per plot for data collection on growth, yield, diseased incidence and severity. The results showed that irrespective of the planting season, all the growth parameters of the climbers, with the exception of the number of leaves per plant, varied significantly (P = 0.05) with beans variety. The highest plant height (171.6 cm), number of grains per pod was highest (8), the highest pod length (13.3 cm) and the least mean number of branches per plant (4) was recorded with the variety PNN. All yield and yield components were found to vary significantly (P = 0.05) with the bean varieties. The highest yield (3.0 Mg/ha) was recorded by MCX. Disease incidence and severity did not vary significantly (P = 0.05) across varieties. Disease incidence and severity were significantly higher in the early planting season (91.7% and 37.7% respectively) than in the late planting season (69.4% and 16.7% respectively). Cultivation of beans should be done in the late planting season, using MCX variety with high yield.

Influence of time of introduction and proportion on the efficacy of grain amaranth trap crop against Aulacophora foveicollis and Epilachna chrysomelina on cucumber (Cucumis sativus L.)

A field experiment was conducted in the early and late planting seasons, 2019 to evaluate the effectiveness of grain amaranth (Amaranthus cruentus L.) planted at different timing and proportion as a trap crop for reducing insect pest densities on cucumber. Amaranth was established into cucumber plots two weeks before cucumber (2WBC), same day (SD) with cucumber or two weeks after cucumber (2WAC) in 100:0, 100:25, 100:50, 100:75 and 100:100 cucumber-amaranth proportions. Amaranth planted 2WBC or SD trapped significantly higher numbers of Aulacophora foveicollis and Epilachna chrysomelina compared to 2WAC, corresponding to lower infestations and damage on cucumber, with the highest fruit yield at SD cucumber. While leaf damage was reduced by 68–74% at 100:100, yield increase of 66–69% was obtained at 100:50 relative to sole cucumber plots. Hence, planting grain amaranth SD with cucumber at 100:50 cucumber-amaranth proportion has a great prospect against insect pests of cucumber in a trap–cropping strategy.

Effects of Planting Pre-Germinated Buds on Stand Establishment in Sugarcane

Sugarcane (a complex hybrid of Saccharum spp.) is propagated vegetatively by using stem pieces of mature cane with healthy buds. Abiotic and biotic stress may cause pre-germination of these buds, which may have an impact on both emergence and plant cane stand establishment. There is very limited information available in the literature. A greenhouse study was conducted with single-budded seed pieces of three levels of bud germination (ungerminated buds, Pop-eyes, and Lalas) from three different cultivars (CP 96-1252, CPCL 05-1201, and CPCL 02-0926) planted in pots and repeated over time. Data on growth parameters (tiller count, primary shoot height, SPAD, and dry biomass of shoots and roots) at early growth showed that Lalas produced more tillers and higher shoot dry biomass than Pop-eyes and ungerminated buds. Both Lalas and Pop-eyes produced higher root dry biomass than ungerminated buds in one of the two experiments. The cultivar had a significant effect on primary shoot height and SPAD. A small plot field experiment was conducted with cultivar CP 96-1252 to validate the results of greenhouse experiments, and similar results were reported for tiller count. The results indicate that pre-germinated buds may have a neutral or positive effect on early sugarcane growth and establishment. Further on-farm research needs to be conducted to confirm these results before using pre-germinated buds as a potential seed source for the late season planting of sugarcane.

Seasonal evaluation of yield and yield component traits of thirteen okra genotypes in a derived savannah

Ten improved okra genotypes obtained from National Institute for Horticultural Research and Training, Okigwe, Nigeria and three local cultivars were evaluated under early and late planting seasons of 2014 and 2015. The aim of this study is to estimate the relationship and magnitude of direct effects among the traits as well as determine the degree of heritability and variability among the genotypes. Genotypic stability analysis was also performed on the yield and the two traits most related to yield. ‘Ele Uhie’ genotype had the highest values for most of the parameters measured for both early and late planting seasons. Among the improved genotypes, ‘TAE 38’ had relatively appreciable yield. In both seasons, all the traits studied showed positive and significant (p < 0.01) correlation with total fruit yield, although number of fruits/plant and plant height at maturity had the strongest relationship. The yield stability estimates showed that the genotypes independently expressed their traits in the four different stability groups. Path coefficient analysis revealed that number of fruits/plant and plant height at maturity had higher positive and higher magnitude of direct effect than the direct effects of the associated parameters studied for both planting seasons. Thus, selecting ‘Ele Uhie’, ‘Ele Ogwu’, ‘Ele Ndu’ and ‘TAE 38’ genotypes with relatively stable and high number of fruits/plant and plant height at maturity would have greater impact in sustaining high yields in okra.

No Evidence Sowing Date Influences Optimum Plant Density of Sweet Corn Grown in the Midwestern United States

Sweet corn (Zea mays L.var. rugosa or saccharata) is sown across a wide range of dates to provide a steady supply of marketable ears for fresh market and processing. There is a perception in the sweet corn industry that plant density tolerance declines in late-season plantings in the midwestern United States; however, publicly available data to support this perception cannot be found. Using field experiments, the objectives of this research were to quantify the effect of the sowing date on growth responses to plant density and determine the extent to which the sowing date influences the optimum plant density and maximum yield/profit. There were few main effects or interactions of the sowing date on crop growth. More importantly, there was no effect of the sowing date on the economically optimum plant density or plant density that optimized yield. Although variations exist in sweet corn optimum plant densities in the midwestern United States, these variations are likely driven by several factors other than the sowing date that have not yet been fully characterized.

Assessment of combining ability comprising alc, nor and rin mutant alleles of tomato under main and late planting seasons

Seventy four genotypes of the tomato (14 lines, four testers of ripening mutant and their 56 F1 crosses developed in line ? tester mating fashion) were appraised under main (E1) and late (E2) planting season at Department of Vegetable Science, Punjab Agricultural University, Ludhiana, Punjab, India. To find out few general and specific combiners, if some, which might be utilized in furthermore breeding programmes to prolong the fruit harvesting span of tomato in the Punjab conditions. The findings hinted in general, the particular parent or hybrid could not be used to assess all examined characters with same efficiency. In main (E1) season line, FL-556 was found best general combiner for average fruit weight, locules number, pericarp thickness, P/E ratio, dry matter and lycopene content; PAU 114 for average fruit weight, lesser locules, pericarp thickness, TSS and dry matter. During late (E2) planting season line, Punjab Ratta found with good GCA values for average fruit weight, lesser locules number, pericarp thickness and TSS content; Roma for average fruit weight, locules number, pericarp thickness and P/E ratio. Similarly tester, alc-IIHR-2050 for pollen viability, minimum days from transplanting to first harvest, harvesting span, average fruit weight, pericarp thickness and P/E ratio in main (E1) season while, for pollen viability, average fruit weight, pericarp thickness and P/E ratio in late (E2) season. The received results furthermore illustrated the best combinations that possessed significant values of SCA which effectively combine to develop a cross with good performance. In main (E1) season from combinations, F1 hybrid SMZ-867 ? rin-Rutgers were registered with best specific combiner for pollen viability, average fruit weight, lesser locules number, Pericarp thickness and P/E ratio; PAU 2381 ? nor-RM-1 for harvesting span, average fruit weight, pericarp thickness, total fruit yield and lycopene content. Likewise, in late (E2) season cross, SMZ-867 ? nor-RM-1 for pollen viability, minimum days from transplanting to first harvest, harvesting span and fruit yield; LT-44 ? alc-IIHR-2050 for pollen viability, average fruit weight, lesser locules and pericarp thickness.

Identity and Pathogenicity of Fungi Associated with Root, Crown, and Vascular Symptoms Related to Winter Squash Yield Decline.

Winter squash (Cucurbita maxima cultivar Golden Delicious) produced in Oregon's Willamette Valley for edible seed production has experienced significant yield losses because of a soilborne disease. The symptoms associated with this disease problem include root rot, crown rot, and vascular discoloration in the stems, leading to a severe late season wilt and plant collapse. Through field surveys, Fusarium oxysporum, F. solani, F. culmorum-like fungi, Plectosphaerella cucumerina, and Setophoma terrestris were identified to be associated with diseased tissues, and each produced symptoms of root rot, crown rot, or stem discoloration in preliminary pathogenicity trials. In this study, 219 isolates of these species were characterized by molecular identity analyses using BLAST of the internal transcribed spacer and translation elongation factor 1 alpha genomic regions and by pathogenicity testing in outdoor, large-container trials. Molecular identity analyses confirmed the identity of isolates at 99 to 100% similarity to reference isolates in the database. In pathogenicity experiments, F. solani produced the most severe symptoms, followed by F. culmorum-like fungi, F. oxysporum, P. cucumerina, and S. terrestris. Some treatments of mixed-species inoculum produced symptom severity greater than what was expected from individual species. In particular, the mixture of F. culmorum-like fungi, F. oxysporum, and P. cucumerina and the mixture of F. culmorum-like fungi, F. solani, and S. terrestris had symptom ratings as high as that of F. solani by itself. Results indicate that this soilborne disease is caused primarily by Fusarium solani, but interactions between the complex of F. solani, F. culmorum-like fungi, F. oxysporum, and P. cucumerina can exacerbate disease severity.

Seasonal difference in fall armyworm Spodoptera frugiperda (Lepidoptera: Noctuidae) abundance and plant injury on selected maize varieties in Ibadan, Southwest Nigeria

The fall armyworm, Spodoptera frugiperda J.E Smith, is a highly destructive insect pest of maize that first invaded Africa in 2016 and has since posed additional constraints to maize production and food security in the region. This study thus investigated the seasonal difference in the abundance of S. frugiperda egg masses and larvae on 25 maize varieties during the early and late planting seasons of 2018 and 2019 in Ibadan, southwest Nigeria. The relationship between larva abundance and foliar damage was also investigated at three-, five- and seven weeks after planting (3WAP, 5WAP, and 7WAP). Results showed that abundance was higher in 2018, in the early season, and at 3WAP. Though foliar damage occurred weekly in both seasons, the relationship between foliar damage severity and larva abundance at 7WAP was consistently weak and insignificant. Also, in both seasons, most of the observed kernel damage was caused by stem borer and not fall armyworm larvae. To make timely fall armyworm management decisions, regular field scouting, especially within the first three weeks after planting, is recommended.

Diallel analysis of selected yield-contributing traits in Okra [Abelmoschus esculentus (L.) Moench

Information on gene action controlling quantitative traits is important for effective selection. A five-parent diallel cross, which generated 10 F1 hybrids of okra (Abelmoscus esculentus) were evaluated during the early and late planting seasons of 2019 in Ibadan, Nigeria. Data obtained were subjected to diallel analysis and genotype by yield-trait (GYT) biplot analysis to estimate combining ability effects and identify stable hybrids for measured traits respectively. Genotype mean squares were significant (p≤0.01) for all most measured traits. Furthermore, General Combining Ability (GCA) and Specific Combining Ability (SCA) mean squares were significant (p≤0.05/0.01) for most measured traits, indicating the influence of additive and non-additive gene actions in expression of these traits. Preponderance of non-additive gene effects shows the high influence of the environment on most of the considered traits in this study. Iwo Nla had the most desirable GCA estimates of -0.98 and 1.14, for days to 50% flowering (DTF), number of fruits per plant (NoF) respectively while IK11 had the most desirable GCA values for mature-fruit width (0.21) and 1000-seed weight (5.71). SCA estimates were most desirable for NH47-4 × LD88, NH47-4 × Iwo Nla, with values of -4.21 and 4.32 for DTF and NoF respectively. Hybrids NH47-4 × Iwo Nla and IK11 × Clemson associated with higher NoF x trait might be useful for improvement of number of fruits per plant in this population.

Comparative Effects of Two Manure Types and Their Combinations on Growth and Yield of Watermelon (Citrullus lanatus (Thunb) Matsum and Nakai) in Nsukka, Southeast Nigeria

Watermelon (Citrullus lanatus (Thunb) Matsum and Nakai) is a high value fruit vegetable that has gained significant importance in Nigeria following the high level of satisfaction derived from its consumption, and the growing awareness of its nutritional and health benefits. However, its production has been limited to northern Nigeria with resultant increase in price of the crop. This study therefore assessed the growth and fruit yield of watermelon as influenced by pig and poultry manure rates during the 2020 late planting season (September to December). The experiment was a 3 × 3 factorial in randomized complete block design (RCBD) with three replications. Three levels of pig (Pg) and poultry (Pt) manures at 0, 5, and 10 t/ha constitutes the factors A and B, respectively. Data were collected on growth and yield attributes, and were subjected to analysis of variance (ANOVA) at p≤0.05, and principal component analysis (PCA) using GenStat discovery 10.3 edition. Correlation analysis was done using IBM SPSS (version 23) [1]. The results showed significant difference (p<0.05) for sole application of varying levels of pig and poultry manures as well as their combinations. For sole application of pig manure, Pg5 gave significantly higher fruit yield (129.2 t/ha) compared to Pg10, and Pg0 (86.8 and 43.8 t/ha, respectively) while Pt10 (109.1 t/ha) outperformed Pt5 and Pt0 (92.1 and 58.5 t/ha, respectively) for sole application of poultry manure. Combination of Pg5 + Pt10 gave the best result for fruit yield (174.4 t/ha) and is thus recommended for watermelon production in Nsukka.

Socio – Economic Impacts of Prolonged Little Dry Season (August Break) in a Climatic Changed Era in Agrarian Communities of Anambra River Basin, Anambra State, Nigeria

The food supply and demand situation for the 2020 fiscal year concerning the main seasonal crops in Nigeria was unpredictable due to the effect of Covid-19 pandemic. Federal and state governments laid much emphasis as a result on agriculture, especially crop production in order to produce food enough to ameliorate hunger, which is one of the negative effects of Covid-19. Nigeria been a rain fed dependent agricultural nation, follows the dictate of weather and other weather elements in her agricultural activities. With climate change and the effect of Little Dry Season, there was a reduction in rainfall in mid-July through August 2020. Rice and Maize which are among the staple foods in Nigeria requires about 750mm to 1200mm of rainfall to thrive. The mean monthly rainfall recorded in our study area (part of Anambra River Basin) consisting of Ayamelum, Anambra West, Anambra East, Oyi and Dunukofia local government areas are 21.15mm and 3.25mm for July, 2020 and August, 2020 respectively. As a result of the shortage of rainfall in these two months, the farmers and the authors observed these negative outcomes which are early maturity of crops; early harvesting of crops as well as poor yields for early season crops. While during the late season planting, farming was affected by the hardening of the ground as a result of absence of rainfall; undissolved fertilizers in farm lands; partial germination of scattered seedlings; Ant, Birds and Rodent infestation and stunted growth. Base on our observation, it was concluded that yields and harvest would be poor and subsequently there would be shortage of food and price hike in food items. The paper recommends for the revitalization of the moribund irrigation facility in Omor, Ayamelum local government area to provide for the shortfall in moisture that is likely to occur in the absence of rainfall.

Incidence and relative abundance of rice stem borers in three selected rice fields in Lagos and Ogun States, Nigeria

This study was conducted to investigate the incidence of rice stem borer infestations and the species composition present in the selected rice fields. Data were collected between April 2017 and November 2018 across three locations, which include the upland rice field in Agbajege, Ogun state, rainfed lowland in Itoikin and Mangrove swamp in Igbogun, Lagos state, respectively. The incidence of rice stem borers was indicated by dead heart and white heads symptoms, while tillers were excised for rice stem borer identification and population. Results showed a high and low incidence of rice stem borers with no significant difference(p>0.05) at p= 0.29 and 0.37 between the early and late planting seasons in the rainfed lowland and upland rice fields respectively. Planting seasons were significant in the incidence of rice stem borers in mangrove swamp rice fields at p<0.05, p=0.01). This study showed that the predominant species of rice stem borers present in the three study sites were Chilo zacconius and Sesamia calamistis. C. zacconius was the most abundant species at 89% while S. calamistis was 11%. Rice stem borer populations were significantly higher at (p<0.05, p=0.000) in flooded zones while the highest rice stem borer populations were observed at the reproductive phase of the rice plants. Thisstudy showed that the planting seasons coincided with the peak period of the development of rice stem borers. Hence, conservation of natural enemies, monitoring and surveillance should be adopted in insect pest management in rice agroecosystems

Assessment of insect pests of sweet potato (Ipomoea batatas L.) and control with botanicals

The high productivity potential of sweet potato is restricted by myriads of insect pests that reduce the quantity and quality of its yield. This study investigated the insect pests of Ipomoea batatas and evaluated extracts from four botanicals namely: Carica papaya, Azadirachta indica, Chromolaena odorata and Moringa oleifera for the control of insect pests of the crop. The vines of two varieties of I. batatas (Shaba and SPK004) were used for the experiment. Aqueous extracts of the botanicals were prepared at 10% w/v and applied as from 4 weeks after planting (WAP) and subsequently at weekly intervals till 10 WAP. Five insect pests infested sweet potato crop in both planting seasons. In the early planting season, the number of insect pests in the plots of Shaba variety of I. batatas treated with plant extracts of C. odorata, C. papaya, M. oleifera and A. indica was 0.7, 0.25, 1.67 and 0.7 respectively and they were significantly (p < .05) lower than the number of insect pests (3.08) in untreated plots. Similarly result was obtained for the effects of other botanicals on the number of insect pests in both early and late planting seasons. The yield of sweet potato (16.14 kg) was highest in the plots of sweet potato treated with extract of C. papaya and it was significantly higher than the yield (2.60 kg) from the untreated plots. The yield from other plots treated with the other extracts were also significantly (p < .05) higher than the yield from the plots not treated with botanicals. The study concluded that the plant extracts can be applied on sweet potato to reduce insect infestation and enhance yield of storage roots.

Soybean yield components at different densities and planting seasons in Paraguay

The aim of this research was to evaluate the performance of soybean cultivars using different population densities and planting seasons. The experiments were established using a completely randomized block design with a 14×3×2 factorial arrangement, where factor A consisted of 14 soybean cultivars, factor B were low (177,700 plants ha-1), medium (266,600 plants ha-1), and high (355,500 plants ha-1) population densities, and factor C consisted of early and late planting seasons. We evaluated the number of pods per plant (NPP), number of grains m-2 (NG), 1000-grain weight (TGW), and yield (kg ha-1). The interaction between cultivar and planting season affected the NG, TGW, and yield. Cultivars DM-6563-IPRO, TMG-7062-IPRO, 6505-B, NA-5909-RG, M-6410-IPRO, DM-6262-IPRO, SOJAPAR-R19, 6806-IPRO, 6205-B, M-5947-IPRO and SYN-1163-RR showed higher yields in the early planting season and cultivar NS-5959-IPRO in the late planting season. Cultivars 5907-IPRO and DM-5958 showed similar yields for the two planting seasons evaluated. The highest yields were obtained from a density of 266,600 plants ha-1. The cultivar×planting season interaction affected the TGW, with the early planting season showing a greater TGW for most of the cultivars evaluated. The NPP depended on the interaction between cultivar, density, and planting season. The combination of the NG and the TGW showed a more significant influence on the generation of yield in the cultivars. This study highlights the importance of selecting genotypes according to their response to variations in planting date and plant density. This information could help Paraguayan farmers to maximize production in the same area, optimizing the available resources.

Effects of Induced Water Stress at the Flowering Stage of Bambara Groundnut (&amp;lt;i&amp;gt;Vigna subterranea&amp;lt;/i&amp;gt; L. Verdc) on Its Yield

Bambara groundnut (<i>Vigna subterranea </i>L. Verdc), a neglected and underutilized legume is one of the main source of plant protein for poor families in tropical Africa, and is capable of contributing to increasing food production in Africa. This present study aimed to see how bambara groundnut respond to induced water stress during the flowering stage. The research was carried out at the Teaching and Research Farm of The Federal College of Agriculture, Akure (FECA), Ondo State, south west zone in Nigeria. The experiment was a split-plot experiment laid out in a Completely Randomized Design (CRD) with three replications during the late planting season of 2020. Data were collected on Plant height, Number of branches, Number of Leaves, Terminal Leaf Length, Terminal Leaf Width (cm), Biomass, Wet Pod Weight/Plant, Dry Pod Weight/Plant, Pod Length, Pod Width, Number of Pods/Plant, Seed Length, Seed Width, Number of Seeds/Plant, and Seed Weight/Plant. Result showed that among the growth parameters evaluated, Number of leaves and branches were significantly influenced by the various induced stress conditions and the control plot recorded the most significant difference. Among the accessions; accession B₈ recorded significantly higher number of leaves across the weeks, while accession B₁ recorded significantly higher number of branches in week 4 and 12 whereas, B₆ recorded against week 8. The interaction C*B₈ recorded significantly higher number of leaves and branches at week 4, whereas at week 8 and 12, the interaction DRT*B₁ recorded significantly higher number of leaves for both weeks, while C*B₆ with at week 8 and at week 12 recorded significantly higher number of branches. For the yield, the result obtained showed that the control significantly (p ≤ 0.05) improved dry seed weight and other yield components (number of pods/plant, number of seeds/plant) of bambara groundnut. The bambara groundnut accessions exhibited differential yield potential. The highest wet and dry seed weight/plant was obtained in the B₄ followed by the B₇ and lowest is the B₁₀. The B₄ out-yielded the other accessions, indicating its high adaptability and suitability to the various induced stress conditions at the flowering stage of the bambara plant.

Aerobic Rice with or without Strategic Irrigation in the Subtropics

Modern rice varieties adapted to aerobic (dryland) conditions have expanded to new rice growing systems thanks to their plasticity in adapting to rainfed and irrigated conditions. This is important because, as water becomes scarce in paddy rice regions (as it is already in Australia), there will be a move towards tropical to subtropical dryland rainfed rice with attendant problems of drought and low temperature. To assess rice adaptability in the wet season of the semi-arid subtropical conditions of coastal central Queensland, field experiments were established for a late season (in January) planting in 2014 and early season planting in November 2015 with 13 varieties developed by Australian Agriculture Technologies (AAT) Ltd were seeded in a vertisol soil. This was to assess their adaptation to rainfed conditions and their response to strategic irrigation. Water scarcity and low temperature prior to and at flowering were important factors constraining yield. Early flowering varieties in the late season planting escaped the otherwise cold and drought stress during the reproductive stage and had higher yields. In the second year, earlier planting made possible with strategic irrigation avoided the low temperature constraint on yield, but without follow-up strategic irrigation, yields were still low. The average yield of varieties increased from 1.5 times (AAT 4) to 16.3 times (AAT 15) with strategic irrigation compared with rainfed yields averaged across years. The increase in yield with strategic irrigation was associated with a greater leaf area index, spikelet fertility, and instantaneous water use efficiency during flowering. Strategic irrigation concentrated roots in the top 15 cm, but differences in yield between varieties under rainfed conditions were not related to root properties. It is important to consider variations in flowering time, yield potential, and drought patterns when developing rice varieties for rainfed semi-arid tropical conditions, as well as when quantifying the benefits of strategic irrigation.

Investigating Organic Manure and Inorganic Fertilizer for Sustainable Maize (Zea mays) Production in Southwestern Nigeria

Aim: This research investigated the utilization of livestock manure as nutrient source in maize farming.&#x0D; Place and Duration: The field experiment was carried out at the research field of the Federal Ministry of Agriculture and Rural Development, Lagos State Field Office, Nigeria during the late planting season (July/August) of 2019.&#x0D; Methodology: An experimental field research was conducted to compare the variation in the vegetative parameters and yields of maize grown with different livestock wastes. The experiment consisted of six treatments, cattle, pig, poultry, sheep manures, NPK and control experiment set-up in a Randomized Complete Block Design with four replicates. The following data were recorded during the experiment: plant height, number of leaves, number of days to first tasselling and silking, number of cob, cob length, effective cob length, cob diameter, cob weight, ear weight, 100 grain weight, grain yield and shelling percentage. Data recorded were exposed to Analysis of Variance (ANOVA) and the means were separated with Duncan Multiple Range Test.&#x0D; Results: The plant height and number of leaves recorded at 9 Weeks After Planting were 215.53, 217.57, 219.69, 188.85, 219.19, 182.76 and 13.60, 13.40, 13.8, 12.4, 13.8, 12.2 cm for cattle, pig, poultry, sheep, NPK and control respectively while the yield were 3193.00, 3055.20, 3513.00, 2855.00, 3791.00 and 1523.80 kg/ha for cattle, pig, poultry, sheep, NPK and control respectively.&#x0D; Conclusion: Considering the yields recorded, it has shown that cattle, pig, poultry and sheep manures are suitable for sustainable maize growth and is a means of livestock waste management.

Bioactivity and effects of spraying interval of selected plant extracts for control of pre-flowering insect pests of watermelon (Citrulus lanatus[Thunb.] Matsum. &amp; Nakai)

This experiment was conducted to determine the efficacy of plant extracts of Tephrosial vogelii Hook. f., Moringa oleifera Lam., Annona squamosa L. and cashew nut (Anacardium occidentale L.) at two intervals of spraying against major pre-flowering insect pests of watermelon. The results show that the effectiveness of each plant extracts depends on the interval of spraying. Plants sprayed at 7-day intervals had significantly less insect infestation when compared with that of 10-day interval of spraying. T. vogelii and M. oleifera had higher insecticidal efficacy than A. squamosa and cashew nut extracts but the applied plant extracts had the same insecticidal potential with Lambda-cyhalothrin against the observed insects during late planting season. Therefore, the plant extracts proved to be alternative to synthetic insecticide in the management of insect pests of watermelon at 7-day interval application sequence.