Days After Transplanting Research Articles

NUTRITIONAL ACCUMULATION FOR SALAD AND ITALIAN TOMATOES GROWN IN A PROTECTED ENVIRONMENT

Tomato cultivation in a protected environment is an important tool for increasing yield, quality, and regularity of production. However, nutrient imbalance in this production system can lead to short-and long-term losses. This study aimed to characterize plant growth and nutrient accumulation and export of two tomato hybrids of the Salad (‘Stella TY’) and Italian (‘HS 1188’) groups in a protected environment and determine the accumulated thermal sum. The treatments consisted of evaluation times. Dry mass and nutrient accumulation could be determined by a sigmoidal non-linear model for both hybrids grown in the protected environment. The cumulative nutrient order was K > Ca > N > S > Mg > P > Mn > Zn > Fe > Cu > B for ‘Stella TY’ and K > N > Ca > S > P > Mg > Mn > Fe > Zn > Cu > B for ‘HS1188’, with yields of 105.7 and 103.4 t ha−1, respectively. The accumulated thermal sum was 1851.7 degree days at 126 days after transplanting (DAT).

ZnO nanoparticles as potential fertilizer and biostimulant for lettuce

Zn is an indispensable nutrient for crops that usually presents low bioavailability. Different techniques have been proposed to improve the bioavailability of Zn, including the use of nanofertilizers. The objective of the study was to evaluate the applications of drench (D) and foliar (F) ZnO nanoparticles (NZnO) compared to those of ionic Zn2+ (ZnSO4) in lettuce. The plants cv. Great Lakes 407 was produced in pots of 4 L with perlite-peat moss (1:1) under greenhouse conditions. The treatments consisted of NZnO applications that replaced the total Zn provided with a Steiner solution, as follows: Zn2+ (100%D) (control); Zn2+ (50%D+50%F); NZnO (100%D); NZnO (50%D+50%F); NZnO (75%D); NZnO (50%D); NZnO (75%F) and NZnO (50%F). Four applications of Zn were made with a frequency of 15 days. 75 days after transplant (DAP), the fresh and dry biomass, chlorophyll a, b, and β-carotene, phenolics, flavonoids, antioxidant capacity, vitamin C, glutathione, H2O2, total protein, and enzymatic activity of PAL, CAT, APX, and GPX were evaluated. The mineral concentrations (N, P, K, Ca, Mg, S, Cu, Fe, Mn, Mo, Zn, Ni, and Si) in the leaves and roots of plants were also determined. The results showed that, compared to Zn2+, NZnO promoted increases in biomass (14–52%), chlorophylls (32–69%), and antioxidant compounds such as phenolics, flavonoids, and vitamin C. The activity of enzymes like CAT and APX, as well as the foliar concentration of Ca, Mg, S, Fe, Mn, Zn, and Si increased with NZnO. A better response was found in the plants for most variables with foliar applications of NZnO equivalent to 50–75% of the total Zn2+ applied conventionally. These results demonstrate that total replacement of Zn2+ with NZnO is possible, promoting fertilizer efficiency and the nutraceutical quality of lettuce.

Effect of Growth promoters and Micronutrients on Performance of Onion under Hill Zone of Karnataka

Onion (Allium cepa) is one of the commercial bulb crops cultivated throughout India. Onion has huge demand for its edible bulb and the productivity is to be increased. An experiment was conducted to investigate the influence of growth promoters and micronutrients in bulb yield of onion cv. Bhima Shakti during 2021-22 at experimental block of College of Horticulture, Mudigere under hilly conditions. The experiment was laid out in Randomised block design with eleven treatments and three replications. The treatments consist of growth promoters (GA3 and NAA) applied at 75 ppm, 100 ppm, 125 ppm and micronutrients (ZnSO4 and Boron) applied at 0.25% and 0.50%. Growth promoters and micronutrients made a significant impact on growth and bulb yield of onion. The obtained results showed that plant height (74.52 cm) was significantly higher in T6-GA3@125 ppm at 105 days after transplanting (DAT). Maximum leaf girth (3.23 cm) at 105 DAT, days for maturity (125 days), bulb yield (34.50t/ha) and bulb volume (96.35 cc) were recorded significantly in T5-GA3@100 ppm. The application of gibberellic acid at the concentration of 100 ppm was effective for obtaining higher bulb yield.

Sustainable management of sheath blight in rice (Rhizoctonia solani Kuhn)

A study was done to explore the various strategies to manage sheath blight of rice. During kharif 2018 and 2019, different treatments viz., foliar and soil application of Trichoderma viride, Pseudomonas fluorescens, mustard and radish leaf and their combination were applied at 30 and 60 days after transplanting (DAT), parameters such as disease severity, grain chaffiness, plant height and yield were evaluated at 45 and 75 DAT. Foliar application of propiconazole 25% EC @ 0.1% was most effective (50%-75.01%) followed by soil application of mustard leaf @ 5 kg/plot before transplanting and foliar application of P. fluorescens @ 5 g/L whereas foliar application of T. viride @ 5 g/L (9.64% and 46. 64%) was least effective. The foliar application of propiconazole 25% EC @ 0.1% recorded lowest percent of chaffiness (11-15%), highest yield of 4941.7-4991.7 kg/ha, whereas foliar application of T. viride @ 5 g/L showed highest percent of chaffiness (28.67-36.67%) with 3516.7-3475 kg/ha.

Standardization of planting time, spacing and nutrient management for traditional red-husked scented rice (Oryza sativa) in West Bengal

The effect of planting time (10 July, 25 July and 10 August), spacing (15 cm × 15 cm and 20 cm × 15 cm), and nutrient management [100% recommended dose (RD) of organic, 100% RD inorganic, and 50% RD organic + 50% RD inorganic] of small-grained red-husked scented “Lal Badshabhog” rice was studied during the wet season of 2014 and 2015 in a split split-plot design at Bidhan Chandra Krishi Viswavidyalaya, Kalyani, Nadia, West Bengal, India. Early-planted crop (10 July) produced tallest plants at maturity (160.2 cm) and leaf-area index (LAI) at 84 days after transplanting (DAT) (4.88), but late planting (10 August) resulted in better tiller production at 56 DAT (285.4/ m2 ). Mean light extinction co-efficient (k) of the variety was 0.40 and 0.37 at 56 and 84 DAT, respectively. ‘Lal Badshabhog’ rice planted on 10 August recorded the highest grain yield (2.72 t/ha), which was 3.77 and 12.76% higher over 25 July and 10 July planting, respectively. Close planting (15 cm × 15 cm or 44 hills/m2 ) could improve the grain yield of ‘Lal Badshabhog’ rice by 3.95% (2.63 vs. 2.53 t/ha) over wider spacing (20 cm × 15 cm or 33 hills/m2 ), and application of 100% RD (N 50, P2O5 25, K2O 25 kg/ha) through chemical fertilizers resulted in higher grain yield (2.64 t/ha), net returns (` 32,900/ha) and benefit : cost ratio (2.02) compared to organic or integrated nutrient management. Mean N, P and K uptake by “Lal Badshabhog” rice at maturity was 41.2, 15.8 and 30.3 kg/ha, respectively, and the crop grown under integrated nutrient management (50% RD organic + 50% RD chemical fertilizer) left the field with better residual status (+5.9% N, +28.3% P2O5 and +1.7% K2O) over initial values after 2-year study in Gangetic alluvium soil.

Response of Indian mustard (Brassica juncea) to varying spacing and transplanting in north Gujarat region

A field experiment was conducted at Castor Mustard Research Station, Sardarkrushinagar Dantiwada Agricultural University, Sardarkrushinagar, Gujarat during the winter (rabi) season of 2020–21, to study the response of Indian mustard [Brassica juncea (L.) Czernj.] to different spacing and transplanting schedule in north Gujarat. The experiment was conducted in a split-plot design with 4 spacing in the main plots and 3 transplanting dates in the subplots, that were replicated 3 times. The maximum plant height at harvesting (189.18 cm) and crop-growth rate (11.69 g/plant/day) at 30–60 days after transplanting (DAT) were recorded with narrow spacing of 45 cm × 30 cm and higher dry-matter accumulation at 30 and 60 DAT (11.57 and 71.70 g/plant respectively) were recorded at 60 cm × 45 cm spacing. Indian mustard transplanted at 45 cm × 30 cm spacing recorded significantly higher seed yield (2,187.1 kg/ha), being statistically at par with spacing 45 cm × 45 cm spacing (2,070.4 kg/ha). In terms of seed yield, the crop transplanted on 10 November (2,142.7 kg/ha) outperformed the crop transplanted on 20 November (1,829.0 kg/ha), but it was statistically on a par with the crop transplanted on 31 October (1,996 kg/ha). The higher net returns (`61,227/ha), production efficiency (19.59 kg/ha/day) and economic efficiency (`548.5/ha/ day) were registered at 45 cm × 30 cm spacing. Significantly higher net return realization (`63,596/ha), production efficiency (19.13 kg/ha/day) and economic efficiency (`567.8 /ha/day) were noted under 10 November transplanting.

Influence of Various Biofertilizers on Growth and Biomass of Rooted Cuttings of Casuarina (Casuarina equisetifolia L.)

The present investigation was conducted at College of Forestry (ACHF), Navsari Agricultural University, Navsari, Gujarat, India. The experiment was laid out in a Completely Randomized Design with three repetitions. The cuttings were raised by using IBA @ 25 ppm + NAA @ 25 ppm. After two months of planting of cuttings the rooted cuttings which exhibited uniform growth were treated with different eight treatments of biofertilizers viz., Azospirillum, Phosphobacterium, Azotobacter and their combinations along with three repetitions were studied for six months. The treatment T : 8 Azospirillum + Phosphobacterium + Azotobacter (3.33 ml each/rooted cutting) enhanced shoot length (12.48, 18.89, 24.94, 31.80, 38.65 and 44.97 cm) and collar diameter (3.00, 4.22, 6.36 8.50, 10.29 and 11.23 mm) respectively of new sprouted shoot at 30, 60, 90, 120, 150 and 180 days after transplanting (DAT). The same treatment also recorded maximum values of fresh and dry weight of root (5.62 and 2.58 g plant-1), shoot (51.54 and 18.42 g plant-1) and plant (57.16 and 21.00 g plant-1), respectively at 180 DAT. Moreover, minimum values of above all parameters were noticed in Control. However, at 180 DAT the highest value of root: shoot ratio on dry weight basis was observed in Control (0.26).

Response of Biochar on Growth and Yield of Aman Rice Under Salt Stress

A pot experiment was conducted in Sher-e-Bangla Agricultural University, Dhaka, Bangladesh during aman season, 2018 to assess the effect of biochar on rice (BRRI dhan62) under salt stress conditions. The factorial experiment was laid out in Randomized Complete Block Design (RCBD) with four replications. Three levels of salinity were used viz. Control (S0), 1600 ppm NaCl (S1), and 2800 ppm NaCl (S2) under factor A and four levels of biochar were applied viz. 0 t ha−1 (B0), 2 t ha−1 (B1), 4 t ha−1 (B2) and 6 t ha−1 (B3) under factor B. The salt materials were added on pot in two installments at 20 and 30 days after transplanting (DAT). Exposure to salinity decreased growth and yield of rice including plant height, tillers hill-1, effective tillers hill-1, grains panicle-1, 1000-grain weight, grain yield and straw yield. The magnitude of growth and yield reduction increased with increasing the salinity level. Exposure of 1600 ppm and 2800 ppm NaCl declined the grain yield of rice by 28 and 100%, respectively. Straw yield (18 and 100%, respectively) and other yield contributing parameters declined by these two levels of salinity in the same way. Application of different levels of biochar ameliorated saltinduced damages to a certain extent. Under 2800 ppm NaCl stress, application of biochar extended life duration of rice plant upto 80 DAT, whereas without biochar application rice plant died after 60 DAT. Upon exposure to 1600 ppm NaCl stress, application of 2, 4 and 6 t ha−1 of biochar increased grain yield by 37, 42 and 30%, respectively, compared with the respective salt treatments (without biochar). Biochar enhanced yield of rice under saline conditions by enhancing yield contributing attributes including effective tillers and 1000-grain weight and by reducing salt-induced damages. However, response of 4 t ha−1 of biochar was best among the biochar levels (2, 4 and 6 t ha−1 of biochar) under both saline and non-saline conditions. Bangladesh Agron. J. 2022, 25(1): 105-113

Influence of crop-establishment methods and weed-management practices on weeding efficiency and productivity of basmati rice (Oryza sativa)

A field experiment was conducted on sandy clay loam soil at the research farm of Sher-e-Kashmir University of Agricultural Sciences and Technology, Jammu, Chatha, Jammu and Kashmir during the rainy (kharif) season of 2016 and 2017, to study the response of different establishment methods and weed management practices on basmati rice (Oryza sativa L.). The experiment comprising 3 establishment methods and 5 weed-management practices with 3 replications was laid in split-plot design. Among establishment methods, system of rice intensification (SRI) though at par with conventional transplanted rice (CTR) showed significant reduction in weed population, weed dry weight and nutrient uptake by weeds at 40 and 60 days after transplanting (DAT) over direct seeded rice (DSR). Likewise, for weed-management practices, application of pendimethalin 1 kg a.i./ha as preemergence (for DSR) or butachlor 1.5 kg/ha as pre-emergence (for CTR) followed by (fb) bispyribac sodium at 25 g a.i./ha at 25 DAS/DAT recorded significantly lower weed density (no./m2 ), weed biomass (g/m2 ) at 40 and 60 DAS/DAT and weed nutrient uptake at 60 DAS/DAT. However, this treatment was at par with pendimethalin 1 kg a.i./ha as pre-emergence (for DSR) or butachlor 1.5 kg/ha as pre-emergence (for CTR) fb 2 mechanical weedings at 20 and 40 DAS/DAT. The same treatment recorded the highest weed-control efficiency (75.28%). Plant height and number of tillers at 60 DAS/DAT and at harvesting effective tillers/m2 , filled grains/panicle, 1,000ˆgrain weight (g) as well as grain and straw yields were significantly higher in SRI over DSR, but at par with CTR. Pendimethalin 1 kg a.i./ha as pre-emergence (for DSR) or butachlor 1.5 kg/ha as pre-emergence (for CTR) fb 2 mechanical weedings at 20 and 40 DAS/DAT recorded significantly higher values over other treatments but at par with pendimethalin 1 kg a.i./ha as pre-emergence (for DSR) or butachlor 1.5 kg/ha as pre-emergence (for CTR) fb bispyribac sodium at 25 g a.i./ha at 25 DAS/DAT for plant height at 60 DAS/DAT, and at harvesting for effective tillers/m2, filled grains/panicle, 1,000-grain weight (g) as well as grain and straw yields. The SRI resulted in the highest net returns (`74,810/ha) and benefit: cost (B:C) ratio (1.63) among the establishment methods, whereas pendimethalin 1 kg a.i./ha as pre-emergence (for DSR) or butachlor 1.5 kg/ha as pre-emergence (for CTR) fb 2 mechanical weedings at 20 and 40 DAS/DAT among the weed-management methods fetched the highest net returns (`60,639/ha) and B : C ratio (1.36).

Temporal soil fertility with organic nitrogen sources in acidic soil of Meghalaya

A field experiment was conducted at CAU, Umiam, Meghalaya during kharif 2017 to investigate the effect of nitrogen application through urea and Azolla on temporal soil fertility build-up under low land rice cultivation at 30, 60, 90 days after transplanting (DAT) and at maturity in acidic soil. The experiment consists of six treatments with and without Azolla incorporation laid out in RBD with four replications. The application of 60 kg N/ha through urea along with Azolla incorporation @16000 kg/ha (T6) recorded highest available N (289.98 kg/ha) after harvest which was significantly superior over control (227.45 kg/ ha) with 9.1% increase. Similarly, this treatment recorded highest available P, K and OC i.e. 20.6, 192.3, 2.1 kg/ha after harvest followed by T5 and T2. Further, it was also observed that available P, K and OC in T6 were statistically significant over T4 whereas T5 was significant over T3 with respect to advancement in crop age.

Morphological Characterization and Adaptive Trail of Two Prominent T. Aman Rice (Oryza sativa L.) Lines under Different Locations of Bangladesh

Two advanced lines: BR8693-8-4-2-1 and BR8693-17-6-2-2, along with BRRI dhan49 (S. Ck) and BRRI dhan33 (R. Ck) as checks were tested at farmers’ field in eight locations such as West Byde (BRRI Gazipur), Khulna (Dumuria), Habiganj (Sadar), Chapainawabganj (Gomostapur), Rangpur (Sadar), Feni (Dagonbhuyan), Chattagram (Hathazari) and Barishal (Sadar) during the season of Transplanting Aman 2018. The trial was replicated three times in each location. The unit plot size was 17.94 m2 (4.6m x 3.9m). Seeding emergence for eight locations varied from 11-17 July 2018. Seedling age varied from 25-30 days among the locations. Seedlings were transplanted at 20 cm x 15 cm spacing. NPKS and Zn fertilizers were applied at the rate of 0, 15, 50, 12 and 3.6 kg ha-1, respectively. All fertilizers except urea were applied as basal whereas, urea was applied in 3 equal splits at 10, 25 and 40 days after transplanting (DAT) Other standard management practices were followed as and when necessary. No insecticide was used because the two advanced lines were insect resistant and diseases were not controlled (to identify susceptibility and tolerance level of lines). Date of seeding, transplanting, flowering and maturity, lodging tolerance, pest and disease incidence, phenotypic acceptance at vegetative and ripening stage, yield and yield components were recorded. Among the two advanced lines, BR8693-8-4-2-1 line was statistically significant from BR8693-17-6-2-2, BRRI Dhan49 and BRRI Dhan33 respectively and the disease reaction, farmers’ opinion, and special character of insect resistant, BR8693-8-4-2-1 was found to be superior for further variety trial. The main purpose of the experiment is to recommended insect resistant rice genotype for proposed variety trail. For yield estimation, 9 m2 sample area from each plot was harvested at maturity and grain yields were adjusted to 14% moisture content.

Using Sigmoid Growth Models to Simulate Greenhouse Tomato Growth and Development

Mathematical modeling has been used to describe the characteristics of crop growth. Establishing a growth model can help to better understand the responses of crops to their environment and improve the efficiency of agricultural production. This study establishes empirical growth models to predict the growth of greenhouse tomato. In this study, we collected beef tomato (Solanum lycopersicum cv. ‘993′) growth data over two crop seasons in Taiwan and established growth models by employing the commonly used Gompertz and Logistic curves. Days after transplanting (DAT) and growing degree-days (GDD) were introduced as independent variables and their relationships with five traits, i.e., plant height, leaf area index, stem dry matter, leaves dry matter, and fruits dry matter were determined. The performances of GDD models were slightly better than those of the DAT models. In addition, we inferred five critical points with biological meaning based on the proposed growth models. The critical points estimated by the Logistic model are closer to our expectation than those of the Gompertz model, and they were applicable for the ‘993′ tomato in Taiwan. These results can be used to predict tomato growth and adjust the fieldwork schedule to improve the efficiency of the greenhouse production of tomatoes.

Screening of Fungicides and Botanicals for Controlling False Smut of Rice

The present investigation was conducted in the field laboratory of the Department of Plant Pathology, Patuakhali Science and Technology University during August 2017 to December 2017 to evaluate the efficacy of botanicals viz., neem leaf extract, garlic clove extract, tulshi leaf extract and zinger rhizome extract at 10% concentration and fungicides viz., TALL 25EC, RAI 32.5 SC, TOWIN 50 WP, Syconazole 25SC and Y-Thane M-45 at 0.2% concentration to control rice false smut disease. The experiment was set up in a Randomized Complete Block Design (RCBD) with 3 replications. Among the treatments RAI 32.5 SC= Suspension concentrate and tulsi leaf extract performed better in respect of percent hill infection and it was 0.51%, 1.03%, 1.28% and 1.79% respectively at 85, 95, 105 and 115 days after transplanting (DAT). Result showed that the lowest percent plant and panicle infection at different days after transplanting were highest in the plot treated with RAI 32.5 SC followed by garlic extract. RAI 32.5 SC showed minimum percent infected grains which were 0.26%, 1.03% and 1.17% at 85, 105 and 115 DAT respectively and maximum 1.22%, 2.39% and 2.99% respectively, in the control plot at 85, 105, and 115 DAT. The highest thousand grain weight (114.6) and yield (4.790) were obtained in RAI 32.5 SC and the lowest thousand grain weight (108.3) and yield (3.587) harvested from the control plot.

Efficacy of pre- and post-emergence herbicide combinations on weed control in no-till mechanically transplanted rice

No-till mechanized-transplanted rice was evaluated for different combinations of pre- and post-emergence herbicides to determine feasible, economically viable weed management options to control complex weed flora in rice fields. All pre-emergence herbicides significantly reduced the population of grassy weeds; of these, pendimethalin resulted in the greatest reductions (83%) at 15 days after transplanting (DAT). Among five post-emergence herbicide treatments, the combination of bispyribac-sodium (10%SP) + pyrazosulfuron (10%WP) was found to be the most effective in controlling all weed flora at both 35 and 55 DAT. The sequential application of pendimethalin (pre-emergence) followed bispyribac-sodium + pyrazosulfuron (post-emergence) resulted in significantly higher rice grain yield (4.4 t-ha−1) and relative gross-margin (417 USD-ha−1) than all other treatments. A strong negative correlation was observed between rice grain yield and weed biomass, and a strong positive correlation between rice grain yield and weed control efficiency. Our findings demonstrate the potential to combine pre- and post-emergence herbicides in no-till mechanized-transplanted rice; these findings have applications globally in regions where rice is established by no-till or mechanized transplanting.

ADAPTASI MORPHO-PHYSIOLOGI NILAM (Pogostemon ) TERHADAP CEKAMAN KEKERINGAN

Patchouli (Pogostemon) can live in dry land and produce atsiri oil. Dry land often,experiencing drought but Patchouli can survive , Adaptability patchouli for life in drought stress condition interesting to ivestigate the cause. The aim of this experiment looking for morpho-physiological characteristics of patchouli varieties adaptive to drought stress condition. The experiment with A Randomized Completely Design with four replicates was used in the trial. Five varieties of patchouli namely Aceh Merah, Lhokseumawe,Tapak Tuan, Sidikalang and Girilaya were transplanted into 30 x 15 x 90 cm wood pot and treated with less water to initiate drought stress after transplanted, all pots were saturated with water (until 100% field capacity), and then treated with nowater addition up to 120 days after transplanting (DAT). Parameters observed were: growth and production biomass and proline content in leaf. The results showed that the highest growth and biomass production components were performed by Girilaya andfollowed by Tapak Tuan varieties. While Sidikalang variety was the lowest in productivity. Maximum length of root, fresh weight of root, and proline content in leaf were also found at Girilaya and followed by Tapak Tuan. Data collection on the growth, production, and morpho-physiological characteristics in relation to adaptation level to drought stress indicated that Girilaya, a Java patchouli group (Pogostemon haeyanus Benth), was the most tolerant among varieties tested. While among the Aceh patchouli group (Pogostemon cablin Benth) Tapak Tuan was the most tolerant variety.Keywords : Adaptation, Patchouli, morpho-physiological characteristic, drought stress

Oligochitosan fortifies antioxidative and photosynthetic metabolism and enhances secondary metabolite accumulation in arsenic-stressed peppermint.

The current study was designed to investigate whether application of irradiated chitosan (ICn), a recently established plant growth promoter, can prove effective in alleviating arsenic (As) stress in peppermint, a medicinally important plant. This study investigated how foliar application of ICn alleviated As toxicity in peppermint (Mentha piperita L.). Peppermint plants were treated with ICn (80 mg L−1) alone or in combination with As (10, 20, or 40 mg kg−1 of soil, as Na2HAsO4·7H2O) 40 days after transplantation (DAT), and effects on the growth, photosynthesis, and antioxidants were assessed at 150 DAT as stress severely decreases plant growth, affects photosynthesis, and alters enzymatic (ascorbate peroxidase, superoxide dismutase) and non-enzymatic (glutathione) antioxidants. When applied at 40 mg kg−1, ICn significantly decreased the content of essential oil (EO) and total phenols in peppermint by 13.8 and 16.0%, respectively, and decreased phenylalanine ammonia lyase (PAL) and deoxy-D-xylulose-5-phosphate reductoisomerase (DXR) activities by 12.8 and 14.6%, respectively. Application of ICn mitigated the disadvantageous effects caused by As toxicity in peppermint by enhancing activities of antioxidative enzymes and photosynthesis and increased accretion of secondary metabolism products (EOs and phenols). An enhancement of total phenols (increased by 17.3%) and EOs (36.4%) is endorsed to ICn-stimulated enhancement in the activities of PAL and DXR (65.9 and 28.9%, respectively) in comparison to the control. To conclude, this study demonstrated that foliar application of ICn (80 mgL−1) effectively promoted the growth and physiology of peppermint and eliminated As-induced toxicity to achieve high production of EO-containing crops grown in metal-contaminated soils.

Development of a plant protection UAV and evaluating its efficacy in managing rice leaf folder (Cnaphalocrocis medinalis Guenee.)

Drones (Unmanned Aerial Vehicles, UAV) have revolutionized agriculture by optimizing the use of several farm operations and through reducing input costs. The present study aimed at designing a plant protection UAV and evaluating its efficacy against rice leaf folder. A hexacopter drone was designed by Acharya N G Ranga Agricultural University and designated as “ANGRAU Pushpak-01” with certain specifications and Payload Data suitable for plant protection spraying in rice. Field studies were taken up during kharif seasons (rainy seasons) of 2020 and 2021 in farmers fields of Guntur district of Andhra Pradesh, India on transplanted rice. The test insecticide used in the present study was flubendiamide 480 SC (39.35% W/w). The UAV hexacopter was optimized for its forward flight speed, height of aerial spraying for delivering spray width and for obtaining maximum spray width using standard protocols. Field studies involved five treatments (four replications), a) 100% RDP (recommended dose of pesticide) with UAV, b) 75% RDP with UAV, c) 50% RDP with UAV, d) 100% manual spray with human back pack motorized spray, and e) water spray using UAV in a RCBD fashion. Nursery was raised during both seasons of study and 30-days-old seedlings were transplanted into main fields and treatments were imposed with flubendiamide spray at 60 days after transplanting (DAT). Leaf folder damage was assessed at prior to flubendiamide spray treatment-wise, then periodically and finally at 10 DAS (Days after spray). Grain yields were harvested replication-wise, pooled and assessed treatment wise for both the field studies in successive years. Our results on optimization of spray technology indicated that aerial spray with UAV at a height of 0.6 m above canopy was ideal in delivering maximum spray width. Further, at this height, there was good amount and uniform distribution of flubendiamide as evaluated by HPLC. The flubendiamide at 75% UAV spray could yield uniform deposition on rice canopy (top, medium, and bottom), and is equally effective compared to 100% UAV spray of flubendiamide. Further, UAV sprays at both these concentrations are more effective in terms of droplet distribution compared to 100% UAV spray with human back pack motorized spray. Field studies indicated that leaf folder damage was effectively reduced with flubendiamide sprays at 100% and 75% RDPs with UAV with no significant differences. However, these treatments were significantly superior to 100% RDP of spray using human back pack sprayer. Similarly, grain yields were significantly superior in 100% RDP and 75% RDP-UAV sprayed plots with no significant differences between them. Further, both these treatments were significantly superior to 100% RDP spray using human back pack sprayer in grain yield enhancement. Overall, our results suggested the efficacy of “ANGRAU-Pushpak-01” UAV hexacopter in reducing leaf folder in rice and enhancing grain yields when sprayed with flubendiamide at 75% RDP, thus offering scope for reduced pesticide costs compared to spraying with 100% RDP of flubendiamide using human back pack motorized sprayer under the conditions evaluated.

Agronomic Performance of Kale (Brassica oleracea) and Swiss Chard (Beta vulgaris) Grown on Soil Amended with Black Soldier Fly Frass Fertilizer under Wonder Multistorey Gardening System

The wonder multistorey garden (WMSG) is an innovative vertical farming system tailored for urban settings that can be constrained by the irrigation regime, and by types and levels of fertilizer application. This study evaluated the effects of applying NPK fertilizer and black soldier fly frass fertilizer (BSFFF) under different irrigation regimes on the growth, yield, and pest infestation of kale (Brassica oleracea) and Swiss chard (Beta vulgaris). The fertilizers were applied at rates equivalent to 371 kg N ha−1. For each crop, the BSFFF or NPK was applied to supply 100% of the N required (100% BSFFF), and then a combination of BSFFF and NPK was applied so that each fertilizer supplied 50% of the N required (50% BSFFF + 50% NPK). Crops’ water requirements were provided using three irrigation regimes: daily, every two days, and every three days. The control treatment was not amended with any fertilizer, while water was provided ad libitum. The results revealed that the irrigation regime significantly affected the leaf production of both vegetables. Irrigation regimes significantly influenced kale plant height, where plants provided with water daily achieved the highest average heights of 20 cm, 46 cm, and 54 cm at 14, 28, and 42 days after transplanting (DAT), respectively. Furthermore, the application of 100% BSFFF produced kale with significantly higher plant heights (55 cm) and number of leaves (9.9 leaves) at 42 DAT compared to other treatments. The interaction between irrigation regimes and fertilizer significantly influenced kale height at 14 DAT and 42 DAT. Use of daily irrigation regime and 100% BSFFF produced the tallest kale plants of 59 cm at 42 DAT. Application of 50% BSFFF + 50% NPK or 100% BSFFF with daily irrigation achieved the highest values of kale and Swiss chard leaf chlorophyll concentration, recorded at 42 DAT. Fertilizer application significantly affected pest population, with the lowest pest infestation being recorded from kale and Swiss chard grown in soil amended with BSFFF. The application of 100% BSFFF or NPK, together with daily irrigation, significantly increased the fresh shoot weight and leaf dry matter of kale and Swiss chard, as compared with the control. The fresh shoot yields of kale and Swiss chard achieved through using a combination of 100% BSFFF and daily irrigation were 14–69% and 13–56% higher than those of NPK, respectively. The same treatment combination also produced kales and Swiss chard with 8–73% and 16–81% higher leaf dry matter compared to NPK, respectively. It was noted that soil amendment with BSFFF maintained higher values of kale (41–50%) and Swiss chard (33–49%) leaf dry matter compared with NPK treatments, during periods of water stress. Our study has demonstrated the high potential of single (100% BSFFF) or combined applications of BSFFF (50% BSFFF + 50% NPK) with a daily irrigation regime to improve the growth, yield, and pest management in Swiss chard and kale under vertical farming. Our study advocates for the scaling of WMSG and BSFFF for sustainable food systems in urban settings.

Effect of moderate salinity on Golden Thistle (Scolymus hispanicus L.) grown in a soilless cropping system

• Soilless cultivation of S. hispanicus l. improved plant growth and yield characteristics. • S. hispanicus L. was resilient to moderate salinity until 90 days after transplant. • Salinity level of 10.0 and 15.0 mM improved functional quality characteristics. • Physiological indicators significantly declined at salinity levels of 10 and 15 mM NaCl. Selecting salt-tolerant crop species for cultivation might be a feasible option to maintain crop productivity in arable lands affected by salinity. In this context, here we examine the responses of the wild edible green golden thistle ( Scolymus hispanicus L.) to moderate levels of salinity when grown in a soilless system for culinary use. Treatments were obtained by establishing four NaCl concentrations (0.5, 5.0, 10.0, and 15.0 mM) in a standard nutrient solution, resulting in initial solution electrical conductivities (EC) of 2.2, 2.8, 3.2, and 3.8 dS m − 1 , respectively. By the end of the experiment, 120 days after transplanting (DAT) drainage EC reached 2.65, 3.33, 3.96, and 4.51 dS m − 1 , respectively. At the first harvest, 90 DAT, the increase of the NaCl concentration had no significant impact on the number of leaves per plant, leaf fresh and dry weight [g plant −1 ], and root dry weight [g plant −1 ]. At the second harvest (120 DAT), 15.0 mM NaCl significantly decreased root and leaf fresh and dry weight without affecting the number of leaves per plant compared to 0.5 and 5.0 mM NaCl, while 10 mM NaCl had no impact on any of these parameters. The concentrations of K + , Ca 2+ , Mg 2+ , and P in the leaves were not influenced by the tested salinity levels, while those of organic-N and NO 3 − -N were significantly reduced by 10 and 15 mM NaCl, 90 DAT. Furthermore, 10 and 15 mM NaCl significantly increased the Cl − and Na + concentrations in leaves, but not in the roots. In the root tissues, only the K concentration was reduced by salinity while P increased at the highest salinity level (15 mM NaCl). Based on these results, we conclude that S. hispanicus L. is resilient to moderate salinity levels and can be considered a promising candidate plant for introduction to soilless cropping systems.

Fenologia de Solidago canadensis L. e Delphinium elatum cultivados em casa de vegetação e associação com variáveis microclimáticas

Abstract Solidago canadensis L. cv. Tara and Delphinium elatum, the hybrid White River are summer flowers with great agronomic potential. The goal of this study was to establish the phenology of these species grown under greenhouse conditions, as well as to determine the correlation between climatic elements (relative humidity - RH, growing degree-days for development - GDD and soil moisture - SM) with growth variables (stem length and diameter, fresh weight FW - and dry weight - DW) in S. canadensis and D. elatum. The life cycle for S. canadensis and D. elatum ended when reaching 30% of the flower opening, the stem length reached 118.05 and 123.74 cm, at 94 and 77 days, respectively. The growth of both species showed a logistic curve pattern throughout the crop cycle; S. canadensis showed maximum values for absolute growth rate (AGR) and relative growth rate (RGR) at 77 and 42 days after transplanting (DAT), respectively; in contrast to D. elatum which occurred at 77 and 28 DAT. On the other hand, for the correlation between climatic elements and growth variables in S. canadensis, the GDD and RH were directly correlated with both FW and DW, stem diameter and length, while an inverse correlation occurred for SM. D. elatum showed a direct correlation between climatic conditions and growth variables.