Split-split Plot Research Articles

Effect of Foliar Application of Potassium and Zinc Elements on Maize Yield and Grain Nutrient Content Under Water-Deficit Conditions

ABSTRACT The valuable corn plant is affected by complications if faced with water deficit conditions, feeding the plant with potassium and zinc elements at the right time can be a useful solution in creating plant resistance. To scrutinize the effect of time of foliar application of potassium and zinc elements on grain yield and concentration of nutrients in maize seed (variety SC 704) under water deficit conditions, a split-split plot experiment was conducted in the form of a completely randomized block design with three repetitions during two crop years at Ahvaz Agricultural Research Station. Treatment of water deficit conditions in the form of irrigation cutting off in two stages of 12 leaves and beginning of tassel emergence with the control treatment was considered as the main plot and foliar application of potassium element in the growth stages (8 leaves, 8 + 12 leaves and without foliar application(control)) was considered as the sub-plot. Also, foliar application of zinc element in the growth stages (8 leaves, 8 + 12 leaves and without foliar application (control)) was regarded as the sub-sub plot. The highest values of yield (1073.8 gr.m-2) was obtained in optimal irrigation treatment with two stages of potassium and zinc foliar application. The highest concentrations of potassium (1.37%), zinc (37.59 mg.gr-1) and protein (15.23%) were accumulated in the seeds when the irrigation was cut off at the tassel stage along with two stages of potassium and zinc foliar application. Phosphorus (0.41%) with two stages of zinc foliar application increased significantly.

Developing a Sustainable Spraying Regime for Cowpea Seed Production in South West Nigeria

Cowpea (Vigna unguiculata L. Walp) production in Nigeria is burdened by insect pest infestations throughout its developmental stages. Farmers rely on the use of conventional insecticides for insect pest control; however, these insecticides are often wrongly used, thereby resulting in undesirable effects on seed yield and the ecosystem. Cowpea was cultivated under different insecticide application regimes and its effect on seed production was evaluated at three substations of the Institute of Agricultural Research and Training, located at Ibadan in Oyo state (Rain forest transiting to derived savannah), Ilora in Oyo state (Derived savannah) and Ballah in Kwara state (Southern Guinea savannah). The trial was conducted during the cowpea cropping seasons of year 2018 and 2019. Ten treatments included 10 sprays of 2.5 EC lambda-cyhalothrin and cowpea varieties Ife Brown and IT2246. The experimental layout was split-split plot in a randomised complete block design. The results show a reduction in percentage aphids infestation as the spraying regimes increased on both cowpea varieties. The lowest values of 1.53 and 1.58% on Ife Brown and IT2246 respectively, were recorded on 200m/ha of four regime spray. Similar results were recorded on the number of thrips, the population of Clavigralla spp and number of pods/plant. Average seed yield under 3 spraying regime increased for both Ife Brown and IT2246 with increase in concentration of pesticide across locations except Ibadan where the yield reduced when the concentration was increased to 600 ml/ha. The spraying regimes of Lambda-cyhalotrin at foliage, flowering and podding have considerable potential for managing the pest of cowpea, but their impact of cowpea grain yield varies significantly.

Impact of Kharif Rice Establishment Systems and Succeeding Tillage Practices on Rooting Behaviour of Succeeding Chickpea, Blackgram and Mustard

Background: The present experiment was designed to evaluate the role of emerging rice establishment systems compared with succeeding tillage practices in supporting the rooting behaviour of chickpea, blackgram and mustard grown in succession. Methods: The current experiment was conducted in kharif followed by rabi during 2021-22 and 2022-23 in a split-split plot design with three rice establishment methods as main plots during kharif followed by two tillage systems as sub plots and in each sub plot, chickpea, blackgran and mustard were grown as sub-sub plot during rabi, after the harvest of kharif rice. Results: Rabi crops grown after dry direct seeded rice following conventional tillage has recorded highest root length and root volume in chickpea (23.83 and 22.97 cm; 13.57 and 13.13 cc), blackgram (20.70 and 20.13 cm; 12.43 and 12.03 cc) and mustard (37.43 and 36.27 cm; 21.50 and 20.80 cc) during successive years of study i.e., 2021-22 and 2022-23, respectively.

Morfometria e rendimento de palma forrageira 'Gigante' sob irrigação e diferentes densidades de plantio

ABSTRACT Growing forage cactus pear in semi-arid regions is an alternative when facing current climate changes, and improving its cropping systems is critical to increasing its yields. The objective was to evaluate morphometric characteristics and yield of ‘Gigante’ cactus pear under complementary irrigation with saline water and different planting densities. The research was carried out in the semiarid region of Bahia during the period from September 2017 to October 2019. A randomized block design was used with treatments arranged in split-split plots. Two irrigation intervals (7 and 14 days) were assigned to plots, four planting densities (20,000; 40,000; 60,000 and 80,000 plants per hectare) to subplots, and four irrigation levels (0, 11, 22 and 33% of ETo) to sub-subplots. High-salinity water (2.91 dS m-1), classified as C4S1, did not limit the growth and yield of ‘Gigante’ forage cactus pear for two crop cycles. Fresh matter and dry matter yields, fresh matter-based water use efficiency and dry matter-based water use efficiency were highest at planting densities of 61,465 and 67,786 plants ha-1, and 61,848 and 69,707 plants ha-1, respectively. The use of 33% ETo irrigation level increased morphometric characteristics, fresh matter yield in the first and second cycles, and dry matter yield in the first cycle. Applying increasing irrigation levels promotes reductions in fresh matterand dry matter-based water use efficiency.

Potassium and phosphorus availability due to fertilization of potassium and organic matter for rice in rainfed rice fields

Serdang Village, Beringin District, Deli Serdang Regency, North Sumatra Province, Indonesia, was chosen as the research location held in May-August 2016. This study aims to determine the relationship between potassium and phosphorus availability, nutrient absorption, and grain yield in rainfed rice fields due to planting time, fertilization, and rice varieties. A split-split plot design with two replications was used in the study. The main plot (a planting time): T1: the 10th day of May; T2: the 20th day of May; and T3: the 30th day of May. Subplot (fertilization): K0: control; K1: 50 kg ha−1 KCl; K2: 5 tons ha−1 straw compost; K3: 2.5 tons ha−1 manure + 2.5 tons ha−1 straw compost; K4: 5 tons ha−1 straw compost + 50 kg ha−1 KCl; and K5: 2.5 tons ha−1 manure + 2.5 tons ha−1 straw compost + 50 kg ha−1 KCl. Sub-subplot (rice varieties): V1: Situ Bagendit; V2: Towuti; V3: Batutegi; V4: Inpago-8; V5: Inpago 9; V6: Inpago 10; V7: Ciherang; and V8: Inpari 10. The data were analyzed using regression and correlation tests. Available potassium and phosphorus, and potassium and phosphorus uptake, were positively correlated with grain yields in all rice varieties grown in rainfed rice fields.

Stimulating growth, root quality, and yield of carrots cultivated under full and limited irrigation levels by humic and potassium applications

Water stress poses a significant challenge for carrot cultivation, leading to decreased yield and inefficient water use efficiency. Therefore, it is crucial to provide plants with suitable supplements that enhance their stress resistance. In this study, we investigated the effectiveness of humic and potassium applications on carrot growth, yield characteristics, root quality, and water use efficiency under varying irrigation levels. A split-split plot experiment was conducted, with two levels of gross water requirements (GWR) (100% and 80%) assigned to the main plots. The subplots were treated with humic acid through foliar application (Hsp) or soil drenching (Hgd). The sub-subplots were further divided to assess the impact of foliar potassium sources (potassium humate, Kh) and mineral applications (potassium sulfate, K2SO4). The results revealed a substantial reduction in carrot yield under limited irrigation, reaching about 32.2% lower than under GWR100%. Therefore, under limited irrigation conditions, the combined application of Hgd and K2SO4 resulted in a significant yield increase of 78.9% compared to the control under GWR80%. Conversely, under GWR100%, the highest average yield was achieved by applying either Hsp and Kh or Hsp and K2SO4, resulting in yields of 35,833 kg ha−1 and 40,183 kg ha−1, respectively. However, the combination of Hgd and Kh negatively affected the yield under both GWR100% and GWR80%. Nonetheless, applying Kh in combination with Hgd under GWR80% led to improved nitrogen, phosphorus, potassium, potassium/sodium ratio, and total sugar concentrations, while reducing sodium content in carrot roots. Based on this study, it is recommended to adopt GWR80% and treat plants with a combination of Hgd and foliar K2SO4. This approach can help plants overcome the negative effects of water stress, improve yield and root quality, and achieve optimal water use efficiency.

Impact of contrasting tillage, residue mulch and nitrogen management on soil quality and system productivity under maize-wheat rotation in the north-western Indo-Gangetic Plains

The sustainability of dominant rice-wheat rotation is under threat due to numerous water-, nutrients-, weeds- and environment-related problems, mainly, due to rice cultivation in north-western Indo-Gangetic Plains (NWIGP) of India. It needs crop- and soil- appropriate management techniques with a focus on conservation agriculture (CA) that can maintain soil health which in turn is essential for long-term sustainability of intensive cereal-based systems. Thus, rice-wheat rotation may be diversified with maize as feasible substitute for rice. But, there is a dearth of comprehensive investigation on the impact of short-term CA in maize-wheat rotation, on soil quality. Hence, an attempt has been made to assess the system productivity (SP) and soil quality in a four-year-old CA-based maize-wheat rotation. Contrasting tillage as the main plot [Conventional tillage (CT), No–tillage (NT)], crop residue mulch as subplot [residue mulch (M+), no residue (M0)], and nitrogen [50 (N1), 100 (N2), 150% (N3) of recommended nitrogen dose] as sub-sub plot was laid out in split-split plot design. Soils sampled from 0–0.05, 0.05– 0.15, and 0.15–0.30 m soil layers were examined to develop a unified soil quality index (SQI) through principal component analysis (PCA) and expert opinion. The available K, P, total organic carbon (TOC), EC, bulk density (BD), dehydrogenase activity (DHA), and soil microbial biomass C (SMBC) were identified as the crucial minimum data set for SQI using PCA. Results showed that, NT and M+ plots had 10.52 and 17.39% higher mean weight diameter (MWD) than CT and M0, respectively at 0–0.05 m soil depth. NT and M+ plots increased TOC by 5.26 and 8% than CT and M0 plots, respectively in 0–0.05 m soil layer. Available K and P were found to be significantly higher in M+ plots than that of M0. NTM+ treatments improved SMBC and DHA than CTM0 treatments. The highest and lowest SQI was registered with NTM + N3 and CTM0N1, respectively. SP was significantly and positively correlated with SQI. Diversification of rice-wheat system with maize-wheat rotation following CA practices appears to have a positive impact on soil health. Therefore, CA-based maize-wheat rotation may be recommended to improve soil quality and system productivity in NWIGP region.

Preferensi Apis cerana terhadap Konsentrasi Gula dan Jarak Dari Sumber Pakan

Apis cerana honey bees are members of the order Hymenoptera, Family Apidae, Sub Family Apinae and Genus Apis. A. cerana bees need feed in the form of nectar and flower pollen (pollen). When the dry season occurs, the availability of natural food sources is difficult to obtain, so alternative feed for bees is very important and necessary. This study aims to determine the concentration of sugar solution preferred by A. cerana bees, to determine the distance to the preferred feed source for A. cerana bees and to determine the direction of the preferred feed source for A. cerana bees. The method used in this research is the split-split plot experimental method with the main plot is the direction, the sub plot is the distance, and the sub-plot is the sugar concentration. The sugar concentration used was 0%, 15%, 35%, and 50%. The distances used are 1 m, 4 m and 7 m which are located in 4 cardinal directions from the bee colony. The data obtained were analyzed using descriptive statistical methods, conservative non-parametric Kruskal Wallis (KW) using SPSS software. The results of this study were the concentration of sugar preferred by A. cerana bees, namely the concentration of sugar 50%, the distance of the preferred feed source for A. cerana bees from the beehive, namely a distance of 7 m, and the direction of the preferred source of feed by A. cerana bees from the beehive, namely east direction.

Morpho-physiological and biochemical characterization of African spider plant (Gynandropsis gynandra (L.) Briq.) genotypes under drought and non-drought conditions.

The African spider plant (Gynandropsis gynandra (L.) Briq.) is a nutrient-dense, climate-resilient indigenous vegetable with a C4 carbon fixation pathway. Understanding African spider plant drought tolerance mechanisms is essential for improving its performance in water-stressed areas. The objective of this study was to evaluate the stress tolerance potential of African spider plant accessions based on thirteen morphological, physiological, and biochemical traits under three different water treatment regimes. Eighteen accessions were evaluated over two growing seasons in the greenhouse using a split-split plot design with four replications and three water treatment-regimes namely optimum (100% field capacity), intermediate drought (50% field capacity) and, severe drought (30% field capacity). The results revealed that water regime had a significant effect (P< 0.01) on the accessions for the traits studied. A significant reduction across most of the studied traits was observed under drought conditions. However, proline content in all the accessions significantly rose under drought conditions. The principal component analysis revealed a considerable difference in the performance of the 18 African spider plant accessions under optimum and drought stress conditions. Several morphological and physiological parameters, including days to 50% flowering (r = 0.80), leaf length (r = 0.72), net photosynthesis (r = 0.76) and number of leaves per plant (r = 0.79), were positively associated with leaf yield under drought conditions. Cluster analysis categorized the 18 accessions and 13 measured parameters into 4 clusters, with cluster-1 exhibiting greater drought tolerance for most of the studied traits, and cluster-4 having the most drought-sensitive accessions. Among the accessions tested, accessions L3 and L5 demonstrated excellent drought tolerance and yield performance under both conditions. As a result, these accessions were selected as candidates for African spider plant drought tolerance breeding programs. These findings will serve as the foundation for future studies and will aid in improving food and nutrition security in the face of drought.

Effect of plant distance and cultivation methods on the growth and yield of three sesame cultivars

A field experiment was carried out in Al-Saqlawiyah region, west of Baghdad, during the 2020 agricultural season in silty clay soil to study the effect of planting pattern and the Row spacing on the growth and yield of three sesame cultivars. The experiment was carried out in a split-split plot design according to a randomized complete block design (RCBD) with three replications, where the planting pattern occupied the main plots (seed prose, seedling pattern). The cultivars occupied the subplot (Haad, Sumer, Rafidain,), while the row distance occupied the sub-sub plot (40, 60, 80 cm). The statistical analysis results indicated a significant effect of the cultivation pattern, as the cultivation pattern with seeds prose recorded the highest values in all the studied traits. The seed prose method recorded the highest seed yield (364.5 gm plant-1 ) compared to the seedling method (290.2 gm plant-1 ). There was also a significant genetic variance (P&lt;0.05) in the response of the studied sesame cultivars to the planting pattern treatments and the between-row spacing. The cultivar Haad scored the highest values in most of the studied traits and thus gave the highest seed yield (452.1 g plant-1 ) compared with the rest of the studied cultivars. The row spacing of 80 cm between the lines gave the highest yield (350.4 g plant-1 ). Keywords: plant distance, cultivation methods, growth, sesame cultivars

Sustainable management practices for durum wheat production: Analyzing specific agronomic interventions on productivity, grain micronutrient content, and quality

As compared with single agronomic crop management practices during grain formation, knowledge about integrated agronomic management practices on grain mineral composition and grain technological properties in durum wheat is limited. This knowledge is important for determining management strategies aimed at increasing grain yield without affecting grain nutritional quality. Integrated agronomic practices such as foliar nutrient application × seeding rate × varieties combined with growing locations were investigated to evaluate the dynamics of yield and grain quality traits. Two durum wheat varieties, three-level of micronutrients (i.e. control, FeSO4, and ZnSO4), and four levels of seeding rate (i.e. 100, 125, 150, and 175 kg ha−1) were arranged in split-split plot design under two different growing locations (environments). The main plots were assigned to the varieties, subplots to micronutrients, and sub-sub plots to the seeding rate treatments. Zinc and iron were applied in a form of ZnSO4 and FeSO4 at the early flowering stage, both at a rate of 25 kg ha−1. Results showed a linear increment in biomass (21.5%) and grain yield (23.5%) under a high seeding rate, even though the 1000-grain weight, the number of grains spike−1, spike length, and the number of grains spike−1 were decreased. Higher varietal and environmental response of seeding rate was observed between varieties. The grain protein content, gluten, and zeleyn index decreased as the seeding rate increased. Grain micronutrient content was significantly influenced by seeding rate and varietal difference. The grain protein content was higher in a dryland environment than in a wet environment. A combined use of density-tolerant varieties, high seeding rate, and foliar-based iron application can improve the grain yield from 2.01 to 3.20 t ha−1 under a potential environment. Hence, all stakeholders should consider the genotype (G), environment (E), management (M), and their synergies, as far as grain yield and quality are considered simultaneously.

Effect of Spraying with Zinc and Ascorbic Acid on some Antioxidants of Maize (Zea mays L.) Affected by Heat Shock

Two experiments were carried out during the spring season 2022 in Diyala Governorate to investigate the effect of foliar spraying with zinc and ascorbic acid on some antioxidants of maize. The experiment was carried out in split-split plot system within RBCD design with three levels of temperature (0, 35, 40) °C, three concentrations of zinc (0,100, 200) mg Zn. L−1, and three concentrations of ascorbic acid (0, 100, 200) mg C.L−1. The results showed a superiority concentration of 200 mg.L−1 for each of zinc and ascorbic acid in all studied traits. Which record in proline 5.15 and 5.23 mg.g−1 dw, catalase 49.74 and 49.51 U.min.g−1 fw., and peroxidase 52.16 and 51.74 U.min.g−1 fw respectively, while the heat shock 30°C and 40°C exceeded the level of non-exposure to heat in all characteristics. The results also showed that the binary interaction between zinc and heat, ascorbic and heat had a significant effect on the studied characteristics. The interaction Zn200 XT35 and C200 X35 excelled in all of the study characteristics compared to other interaction, and the results also showed the superiority of the triple interaction treatments Zn200* C200 * T35 in all studied traits.

Bio-inoculated Nutrient Management Influence on Soil Nutrient Availability Pattern and Growth of Hybrid Pigeonpea (ICPH 2740) under Establishment Methods and Crop Geometry

Background: A two-year field study was conducted at the ICRISAT research farm during the rainy seasons of 2021 and 2022 to investigate the impact of crop geometry, crop establishment method and sustainable nutrient management practices on nutrient availability pattern and growth of hybrid pigeon pea. Methods: The experiment followed a split-split plot design. The collected data was analysed using radar graph and heat maps for nutrient availability and dry matter respectively. Result: Data revealing that transplanted plots registered higher nutrient availability and proportionate root and total dry matter production at various growth stages. Among plant geometry the root and total dry matter production was higher with 100×100 cm. when considering planting methods, transplanting with a square system of 100×100 cm, combined with an integrated nutrient management approach consisting of 150% (or) 100% soil test based NPK, vermicompost at a rate of 5 t ha-1, phosphate-solubilizing bacteria (PSB) and seed treatment with Rhizobium, resulted in average of 31.5% higher dry matter production over alone inorganic nutrient management practices. Thus, a square geometry of 100×100 cm, along with sustainable integrated nutrient management (100% soil test based NPK, vermicompost at a rate of 5 t ha-1, PSB and seed treatment with Rhizobium), resulted in higher nutrient availability and dry matter production. These findings highlight the importance of careful selection of planting methods, crop geometry and nutrient management practices for maximizing the nutrient mining for production of high dry matter production of hybrid pigeonpea.

Effect of Soil Types and Sowing Methods on Growth and Yield of Some Varieties of Sesame (&lt;i&gt;sesamum indicum L.&lt;/i&gt;) Grown in Dutse, Jigawa State

A field trial on the effect of soil types and sowing methods on growth and yield of some varieties of sesame ( sesamum indicum L.) was conducted at school farm Federal University Dutse Jigawa state (latitude 11.00̊ N to 13.00̊ N and longitude 8.00̊ E to 10.15̊ E) during the 2019 rainy season. The treatments used were three soil types (Clay, loam, sand) and two sowing methods (drilling and dibbling). Two varieties of sesame namely EX-Sudan and E8 were used. A split-split plot design was used. Result showed that the number of leaves, number of capsules per plant 1000 seed weight and seed yield per plant were significantly affected by sowing method with drilling method producing the highest seed yield per plant and variety had significant effect on number of leaves per plant, days to 50% flowering and maturity and seed yield per plant with EX-Sudan manifesting the highest yield per plant. The interaction between varieties were only significant on number of capsules/plant while between sowing method and variety was only significant on seed yield per plant. Interaction between variety and soil type showed that V1S1 (EX-Sudan and Loamy soil) had the highest influence on plant growth parameters while V2S2 (E8 and Sandy soil) had the lowest. The results indicated that drilling is the best sowing method, loamy soil is the best soil type for growing sesame while the variety EX-Sudan produced the highest seed yield and seed quality of sesame more than the E8 variety. Thus, farmers could be recommended to adopt these agronomic practices using EX-Sudan for increased sesame production in the Sudan savanna ecological zone of Nigeria.

Effect of Irrigation Regimes and Mulching on the Crop Physiology and Yield of Rabi Maize (Zea mays)

Agriculture is a vital sector of India’s economy and plays a significant role in providing food security, employment, and contributing to the country’s overall development. Maize is a crucial crop within the agriculture sector in India. Maize cultivation contributes to crop diversification in Indian agriculture. It serves as an alternative crop option for farmers, reducing dependence on traditional crops like rice and wheat. Diversification helps in maintaining soil health through crop rotation. A field experiment was conducted at the Farm of College of Agricultural Engineering and Technology, Godhra, Gujarat during the year 2018-19, to study the influence of drip irrigation regimes with mulching on the physiological development and yield of the rabi maize (Zea mays L.) in the sandy loam soil of the region of Middle Gujarat. The field experiment design was a split-split plot with 36 treatment combinations with 3 replications including three irrigation regimes (1.0IW/CPE, 0.8IW/CPE and 0.6IW/CPE), four mulch conditions (control, paddy straw, black plastic and reflective silver plastic mulch), and three stages (tasselling, silking and dough stage). The result revealed that as the consumption of water increased, growth parameters, grain yield, and its attributes increased significantly at each higher level of irrigation regimes up to 1.0 IW/CPE with reflective silver plastic mulch under all the stages but 0.8 IW/CPE with black plastic mulch result was comparable to 1.0 IW/CPE with reflective silver plastic mulch. The reflective nature of silver mulch scatters light, ensuring better light distribution throughout the plant canopy. This can enhance photosynthesis and promote more uniform plant growth. Black plastic mulch absorbs and retains heat from sunlight, raising soil temperatures. This is advantageous in cooler climates or during the early growing season, as it promotes earlier germination, faster growth, and improved crop productivity.

Sensory quality and nutritional composition of carrot (Daucus carota L.) genotypes as affected by fertilization in production system in Cameroon

BackgroundRecommendations for fertilizer use in agriculture do not take into account the growing region and the source of the organic matter. In addition, vegetable growers are unaware of the quantities of fertilizer to be applied during cultivation. Accordingly, there are increasing complaints about the poor quality of the vegetables produced which is likely associated to the type and the dose of fertilizer used. Therefore, the objective of this work was to determine the probable origin of poor carrot quality in production basins in Cameroon. The factors consisted of five carrot genotypes and nine fertilizer types arranged in the field in a split-split plot experimental design. The sensory quality of the carrot samples was assessed by a quantitative descriptive test. The nutritional value was determined according to the treatments performed.ResultsThe results of this study showed that both the sensory quality and nutritional value of carrots significantly depend on the variety, and the type and dose of fertilizer used. However, the variety New Kuroda treated with 10 t ha−1 of chicken manure and the unfertilized variety Vanessa F1 were recorded as having the best sweetness and overall acceptability scores. The best nutrient parameters such as total carbohydrate, proteins, ash, cellulose, NDF and ADF were obtained with the carrot varieties New Kuroda grown with a combination of chemical fertilizer (300 kg ha−1) + chicken manure (10 t ha−1), Pamela + unfertilized, Madona fertilized with 10 t ha−1 chicken manure, with 600 kg ha−1 chemical fertilizer + 5 t ha−1 chicken manure or not fertilized, Amazonia fertilized with 300 kg ha−1 chemical fertilizer and Vanessa F1 fertilized with a combination of 600 kg ha−1 chemical fertilizer + 5 t ha−1 of chicken manure.ConclusionCarrots with good sensory quality such as sweetness and deep orange colour were obtained with unfertilized Vanessa F1 variety. The variety Amazonia fertilized with 300 kg ha−1 chemical fertilizer provided good nutritional parameters including carotenoids, fibres, carbohydrates proteins and lipids.

Growth and Yield of Three Soybean Cultivars by the Nutritional Effect of Zinc and Arginine

To examine the impact of foliar feeding with zinc and arginine acid on some physiological and productive traits of soybean cultivars, an experiment was carried out in the fields of a crop in the Al-Khalidiya Island area of Al-Anbar Governorate, at 43° longitude and 33° latitude, in a sandy mixture soil. The experiment was conducted using a randomized complete block design (R.C.B.D), a split-split plot, and three replicates, with zinc concentrations (50.0 and 100 mg ZnL−1) on the main plates, arginine concentrations (40.0 and 80 mg Arl−1) on the secondary plates, and the varieties (D, Shaima, and Lee) on the sub-secondary plates. Results from the experiment are summarized as follows: The highest mean for all traits studied was found with a Zinc concentration of 100 mg Zn l−1, which also outperformed a concentration of 50 mg Zn l−1 and the control treatment. Arginine 40 mg L−1 achieved the highest rate for leaf area and nitrogen percentage in leaves, while 80 mg L−1 gave the highest average for root length (28.77 cm), number of pods per plant, fertility rate per pod (95.39%) and plant seed yield (58.21 g plant−1). Leaf area and pod count were also best for the Shaima variety, whereas root length, pod fertility, and seed output were best for the Lee variety. The leaf nitrogen content of the different cultivars did not differ appreciably.

Effect of row proportions, organic and inorganic nutrient sources on growth and yield of potato (Solanum tubersoum) cultivars

The effects of row proportions and nutrient management was studied in potato (Solanum tubersoum L.) + Indian mustard [Brassica juncea (L.) Czernj.] intercropping system during 2014–15 and 2015–16 at Amar Singh College Farm, Lakhaoti (Bulandshahr), Uttar Pradesh. The field experiment was laid out in a split-split plot design with 3 replications. The main plot treatments consisted of 3 varieties, viz. ‘Kufri Pukhraj’, ‘Kufri Anand’ and ‘Chipsona 3’, and subplots comprised row proportions of 2 : 1 potato : Indian mustard (P : M), 4 : 1 P : M, potato sole and Indian mustard sole and the sub-subplot treatments consisted of 3 nutrient sources 100% organic (FYM), 100% inorganic and 50% organic + 50% inorganic. The maximum fresh weight of tubers (450.33 g), total tuber dry weight (56.99 g), total number of tubers/plant (15.40) as well as total biological yield (49.14) were recorded in ‘Kufri Pukhraj’ both for A - grade and total tuber yield. Row ratio of 2 : 1 (P : M) recorded higher fresh weight of haulms/ plant (191.48), while higher dry weight/plant of potato (119.70) was recorded in the sole crop. Number of tuber/ plant, fresh and dry weight of tubers were significantly higher under sole potato than row ratio of 4 : 1 however, row ratio of 4 : 1 was slightly superior to row ratio of 2 : 1. Sole potato and row ratio of 4 : 1 resulted in significantly higher total biomass than row ratio of 2 : 1. Yield of different grades and total tubers was recorded significantly higher in sole crop than that for row ratio of 4 : 1 and 2 : 1, though variations were observed nominal in case of Cgrade tubers. Significantly higher potato yield (2.85 t/ha) was observed with the application of nutrients through 50% organic + 50% inorganic fertilizer application.

Effect of Treatment with Growth Regulators Gibberellic Acid and CPPU on some Vegetative Traits and Yield of Three Potato Cultivars Solanum tuberesom L.

The experiment was conducted in the fields of the College of Agriculture / University of Tikrit for the spring season 2019 within an area with longitude (43.35 degrees east of Greenwich) and latitude (34.27 degrees north of the equator), to study the effect of treating potato tubers by soaking with gibberellin before planting and spraying with growth regulator CPPU with three levels for each of which (0, 5, 10) mg L−1 in some vegetative growth characteristics and yield characteristics, quantity and quality of three potato cultivars of class A (Barcelona, Laperla, Montreal). The experiment was implemented using split-split plot design within a design Random complete plots (R.C.B.D) and with three replications, the cultivars were placed in the main plot, dipping with gibberellin in the sub-plot, and spraying with CPPU in the sub-sub plot. The results shows that dipping with gibberellin makes significant differences in the leaves number and percentage of seeding that gave (158.98 plant leaf−1 and 7.21%) respectively. As for spraying with CPPU, it was superior in terms of the leaves number, the number of unmarketable tubers, the percentage of seedig and the percentage of protein, and the values were given (157.39 Plant leaf−1, 2.88 Tuber plant−1, 7.24%, and 6.59%) respectively. As for cultivars, the cultivar Laperla excelled in the following characteristics (the leaves number, the ratio of root weight to the weight of vegetative growth, and the percentage of seeding at harvest). The values were (203.05 plant leaf−1, 31.70%, and 5.59%), respectively. As for the double and triple interactions between the treatments, the increase was significant for all the traits taken for the study.

Cobalt Combined with Potassium Humate as Beneficial Applications in Alleviating Water Stress Impacts on Groundnut During Sensitive Growth Stages

Enhancing plant nutrition during critical periods of water stress is a paramount objective. As such, this study aims to examine the effects that arise from implementing water stress regimes during the sensitive growth phases of groundnut. Furthermore, we will explore the impact of applying cobalt and potassium humate individually or in combination, either through foliar application (KH-F) or soil amendments (KH-S), to mitigate the adverse effects on nutrient accumulation, yield, and irrigation water use efficiency (Iwue). A field experiment was conducted between 2021 and 2022 using a split-split plot design. In the main plots, an additional control of full irrigation requirement scheme (IR100) was implemented, along with three other schemes: the first involved applying 75% of the irrigation requirement during the development stage (IRD75), the second applied 75% during the flowering till pod stage (IRF75), and the third involved applying 85% from the development stage till the pod stage (IR85). In the subplots, cobalt was applied at rates of 0 and 7.5 mg l−1 to the plants. The sub-sub plots were further divided to investigate the effects of KH-F and KH-S. Plants that experienced water stress during the flowering stage were found to be more vulnerable. However, when treated with KH-S, there were significant improvements in yield compared to KH-F treatment. This effect was particularly pronounced under the IRF75 irrigation scheme. Interestingly, there was an antagonistic relationship observed between cobalt and iron or manganese, in contrast to other nutrients. When KH-S was applied in combination with cobalt, it showed the potential to enhance various characteristics and increase the uptake of iron or manganese. The highest yield, nutrient accumulation, and Iwue were achieved through the combined application of cobalt and KH-S, along with adopting the IR85% irrigation scheme.