Manual Weeding Research Articles

A green and economical weeds control agent suitable for drone

Weeds are one of the main factors affecting orchard yield, fruit quality and economic benefits. However, present methods have been lower effect and high labor intensity. To inhance the effect of weeds control on orchard, a new green and economic agent suitable for drone with choline chloride and eucalyptus oil as the main components was developed. Adopting optimized “3414” test design, the paper studied the prevention and control effect of this new weed control agent on 8 kinds of main weeds in the orchards of the Yellow-Huai Rivers. The results showed that T5 and T12 were significantly (P≤0.05) control the growth speed of 8 kinds of weeds, T4 was only inhibit the growth of Erigeron canadensis, Digitaria sanguinalis and Artemisia annua, T11 was only inhibit the growth of Tribulus terrestris, Humulus scandens and Cyperus rotundus, and T3 and T13 were promote the growth of weeds, which had the worst control effect among all treatments. Combined with the economic benefit analysis, the cost per 667m2 of weed control of T12 was 124 RMB, which was the most economical compared with manual weeding and mechanical weeding. Therefore, applying 30g choline chloride, 120 mL eucalyptus oil and 75g sucrose ester to each 667m2 is recommended to be popularized as a new green and economical weed control agent in the orchard production of the Yellow-Huai Rivers.

Comparing manual and mechanical weed management techniques for upland organic rice in acidic soil of Meghalaya: A on-farm study

Comparing manual and mechanical weed management techniques for upland organic rice in acidic soil of Meghalaya: A on-farm study

Bio-efficacy of different POE herbicides for broad spectrum weeds management in chickpea (Cicer arietinum L.)

A field experiment was conducted during 2020-21 and 2021-22 to study the effect of different post-emergence (POE) herbicides for broad spectrum weed management in chickpea. The experiment was laid out in a randomized block design with eight treatments and replicated thrice. Treatments comprises topramezone 20.6 g a.i. ha-1 at 14 DAS, topramezone 20.6 g a.i. ha-1 at 21 DAS, topramezone 25.7 g a.i. ha-1 at 14 DAS, topramezone 25.7 g a.i. ha-1 at 21 DAS, quizalofop-p-ethyl 100 g a.i. ha-1 at 21 DAS, unweeded control, weed free check (manual) and imazethapyr + manual weed control (MWC). Among the different herbicidal treatments, topramezone 20.6 g a.i. ha-1 at 21 DAS significantly higher seed yield (1377 kg ha-1) followed by topramezone 20.6 g a.i. ha-1 at 21 DAS (1265 kg ha-1), highest weed control efficiency and also recorded higher return (₹ 45,659 ha-1 ) and B: C ratio (2.73) during 2020-21.

Management of weed diversity through organic mulching and alternative weed suppression practices on ginger (Zingiber officinale)

A field experiment was conducted at the Regional Research Station (Hill Zone), Uttar Banga Krishi Viswavidyalaya, Kalimpong, Darjeeling, West Bengal, during 2019 and 2020 to study the effect of weed diversity, growth and yield of ginger (Zingiber officinale Rose) as influenced by organic mulching and alternative weed management practices. The randomized block design, having seven varying treatments with three replications was used. The treatments consisted of dry weed biomass mulch @ 5.0 t/ha (T1), paddy straw mulch @ 5.0 t/ha (T2), FYM Mulch @ 5.0 t/ha (T3), dry leaves of Schima wallichi@ 5.0 t/ha (T4), dry leaves of Artimesia sp. and Eupatorium sp. @ 5.0 t/ha (T5), hand weeding (twice) at 45 and 90 DAS (T6) and unweeded control (T7). The result showed that hand weeding twice at 45 and 90 DAS (T6) appreciably reduced the total weed population/m2 and total dry weight of weeds than unweeded control plot (T7) at all the stages of crop growth. The highest plant height (82.10 cm), number of leaves/clump (65.41), number of pseudo stem/clump (5.17), rhizome length (7.22 cm), rhizome width (5.50 cm), number of fingers/rhizome (6.42), yield/plant (0.268 kg/plant), yield (20.33 t/ha) and weed control efficiency were recorded under the hand weeding twice at 45 and 90 DAS (T6) compared to other treatments. The results showed that it is necessary to cover the soil surface with different mulch materials and manual weed control practices to achieve a good control of weeds along with enhanced yield attributes and yield.

Effect of integrated weed management in cucumber

1Cucumber (Cucumis sativus L.) is one of the popular vegetable crops of the cucurbitaceae family owing to its uses as a vegetable crop and for its medicinal uses. (Keerthika et al.2016). It is mainly grown for its tender fruits which are used as a salad and for pickling. Fruits act as a coolant and are used in treating jaundice, indigestion and constipation (Mohan et al. 2016). Cucumber faces several production constraints of which competition from weed population for soil, space, water, light and nutrients forces the plant to produce lesser yield. (Osundare et al. 2019) The removal of weed either manually or chemically adds to the cost of cultivation. Manual weeding has been found to be very effective in controlling weed population in cucumber, however, it is very tedious and costlier because of more manpower requirement (Raoand Nagamani 2010).

Weed Management in Linseed: A Review

Slow initial growth makes linseed crop more vulnerable to weed infestation, which requires proper attention to obtain expected plant growth and yield. Control of weeds at early stages play a vital role for attaining robust plant growth that results in higher yield. Depending on location and method of cultivation, various types of weeds such as broad leaf, sedges and grasses are found in linseed field. In linseed crop, weeds can be controlled by manual, chemical or both the methods. As manual weeding is labour intensive and needs more time, chemical method of weed control is preferred to enhance profitability of the crop. Pre-emergence application of herbicide controls the weeds from the initial stage of plant growth that culminates with higher yield and more profit.

Alternate of Manual Weeding Tools: A Research into an Automatic Weeding Control Strategies Enabled by Embedded Systems

A key enabling factor for treating individualized weeds in the crops is the Automatic Weeding Control device (AWCd) as it is being capable of finding and distinguishing weeds in the field. The non-herbicide approaches used to manage weeds are a component of the personalized treatment of weed crops. In this study, mechanical weed control techniques are investigated as an alternative. In this study, three specifications—a cutting mechanism, a head-surface tilling (tines), and a foot-surface tilling (arrow hoe)—are taken into account. With different rates of application to herbicide-resistant, these processes were estimated in a controlled field and the efficacy of the implementation is estimated by using the demographic analysis and also, the importance of early interface has also been highlighted. For all the weeds accounted in this research, Automatic weeding control was found to be very effective thus ended up in overall survival probability.

Efektivitas Herbisida Berbahan Aktif Metil Metsulfuron Terhadap Gulma Pakis Kawat (Dicranopteris linearis) Pada TBM Kelapa Sawit (Elaeis guineensis Jacq) Di Desa Sukoharjo Lahat Sumatera Selatan

One of the causes of low oil palm production is the presence of weeds, so weed control efforts are needed. One of the weed control methods is chemical weed control using herbicides. Methyl metsulfuron herbicide is one of the active ingredients of herbicides. The aim of this study was to obtain the optimal dose of methyl metsulfuron to control wire fern weed (Dicranopteris linearis) in immature oil palm plantations. The method used was a randomized block design (RAK) with
 8 levels of treatment, namely A (methyl metsulfuron 15 g.b.a/ha), B (methyl metsulfuron 50 g.b.a/ha), C (methyl metsulfuron 85 g.b.a/ha), D (methyl metsulfuron 15). g.b.a/ha + adhesive), E (methyl metsulfuron 50 g.b.a/ha+ adhesive), F (methyl metsulfuron 85 g.b.a/ha+ adhesive), G (manual weeding), H (without control and herbicide). All treatments were replicated 3 times. Parameters observed were weed mortality, weed dry weight and phytotoxicity. Data analysis used linear model variance with a significance of 5%, if there was a significant difference, it was continued with the Ducan Multiple Range Test (DMRT) further test. The results showed that the mortality of Dicranopteris linearis weeds with the herbicide methyl metsulfuron 85 g.b.a/ha was significantly different from the treatment with methyl metsulfuron 15-50 g.b.a/ha. Weed dry weight with the herbicide methyl metsulfuron 15-85 g.b.a/ha and manual control was significantly different from that without control. Weed control with methyl metsulfuron herbicide does not cause phytotoxicity.

CONTROL OF CORN POLLUTION IN THE CONDITIONS OF THE RIGHT-BANK FOREST STEPPE

This article presents the results of studies of the main elements and methods of controlling the development of weeds in corn crops and the identified changes in water and nutrient properties of the soil. The optimal tank mixtures and technological combinations of new soil and insurance herbicides have been determined, which provide a high level of technical efficiency on a wide species spectrum of weeds that clog corn crops. In particular, for farm conditions, the complex nature of the formation of the type of weediness, which changes during the growing season of the crop, was noted. The results of assessments of the dynamics of weed vegetation indicate a gradual increase in cenotic tension due to the gradual transition of dominant species of weeds, such as Chenopodium album L., Amaranthus retroflexus L., Echinochloa crus-galli L., Elytrigia repens (L.) Gould , Sonchus arvensis L, Cirsium arvense L., Convolvulus arvensis L. in the middle tier of sowing with a simultaneous increase in the frequency of their determination by 1.1-1.3 times. It was established that the best growth and development of the total leaf surface of corn plants (2.15-2.26 pcs./m2) was noted on the herbicide agro background and complete removal of weeds, and with natural weediness of the crops - a negative effect on growth processes, size and duration of functioning of leaves (1.14 pcs./m2). According to the research results, the technical efficiency against weeds of the first wave reached 100% when combining soil and insurance herbicides - Dual Gold - 1.5 l/ha (before sowing) + Stellar - 1.25 l/ha + Surfactant Metolate - 1.25 l/ha (by stairs); during the second and subsequent waves of weeds, protection systems that combine vegetative and soil deterrent effects are best controlled (Stellar - 0.8 l/ha + Akris - 1.5 l/ha + Surfactant Metolate - 0.8 l/ha and Kelvin Plus - 0.3 kg/ha + Akris - 1.5 l/ha + PA Hasten - 1 l/ha). The highest yield of corn grain (6.98 t ha-1 and 6.81 t ha-1) was obtained from the combination of soil and insurance preparations Akris (before sowing) + Kelvin Plus and PAR Hasten (after the steps) and Dual Gold (before sowing) + Stellar and surfactant Metolat (by stairs); Akris + Stellar + metolat surfactant (yield - 6.68 t ha-1) was singled out among post-emergence herbicide mixtures; with autonomous use of the preparations Stellar and Kelvin Plus, the yield was 6.35 t ha-1 and 6.22 t ha-1, respectively. The identical economic expediency of using such variants of herbicide application on corn Akris, 1.5 l/ha + Stellar, 0.8 l/ha + Metolat surfactant, 0.8 l/ha and Stellar, 1.25 l/ha + Metolat surfactant, has been confirmed ,1.25 l/ha, which was 43% higher than in the control with natural weeding and 33.2-33.4% higher than in the option of inter-row cultivation with manual weeding.

Weeds Detection and Control in Rice Crop Using UAVs and Artificial Intelligence: A Review

Weeds are serious issues in rice farming and undesired plants that compete for water, light, space, and nutrients, reducing crop yields. Weeds competition in rice crops can result in yield failure of up to 100% if weeds are not controlled. Furthermore, weeds will raise protection costs by harbouring other pests such as diseases, insects, and nematodes that use weeds as alternate hosts. Rice fields are infested with grassy weeds, broadleaves, and sedges, among other weeds. Weeds detection is important to identify the types of weeds in rice areas and make the precise decision to determine the method of weeds control and reduce herbicide use. Chemical, biological, and mechanical weed control strategies such as manual weeding, mechanical weeding, and herbicide use are all part of the Integrated Weed Management (IWM) approach. In the rice field, however, pesticide spraying to eliminate the weed is a very common control approach. Still, this method has become ineffective due to frequently spraying with the same type of herbicide. Early detection is required to define the type of weeds in rice fields, make a precise decision on weed management methods, and prescribe the appropriate herbicide to the rice farmer. Artificial intelligence and unmanned aerial vehicles (UAVs) were largely applied to identify the weeds in rice fields and herbicide spraying to control the weeds. UAVs, such as drones, have recently shown to have a lot of potential in agriculture, such as crop health monitoring systems, assisting in planning irrigation schedules, estimating production data, and capturing weather analysis data and weed infestation. In Malaysia, UAVs are mostly utilized for nutrition and pesticide applications, particularly by smallholder farmers and industries. The integration use of artificial intelligence including unmanned aerial vehicles drones, and various sensors, hyperspectral, multispectral, and RGB (red-green-blue) cameras, thermal and odor sensor for weed early detection methods could ensure the possibility of a better outcome in managing weed problems. This paper reviews the detection and controlling of weeds using UAVs and artificial intelligence technologies in rice crop.

Finite Element Analysis (FEA) of blade weed design using Ansys workbench

Manual, semi-conventional, and conventional weed eradication are the three forms of weed eradication utilized. Farmers benefit greatly from the usage of weeding equipment in combating pests in the fields. The blade you use determines how successful you are at weeding. As a result, it is required to examine the weeding weeds blade. With a tetrahedral mesh, simulation utilizing the finite element analysis approach allows for the optimization of design, computation, and prediction of material strength. The goal of this research was to figure out how much von Mises's stress, deformation, and safety factor were worth. ANSYS Workbench software was used to simulate various loadings of 10N, 25N, and 50N. The highest von Mises stress created by simulation of modelling weed blades at 10N, 25N, and 50N loads is around 2.95x10-2 MPa, 7.38x10-2 MPa, and 0.14755 MPa, respectively. Each of the safety factors is 15, and the maximum deformation value is 4.26x10-7mm; 1.06x10-6mm; 2.13x10-6mm. The safety factor indicates that the weed weeding knife design is safe to use up to 50N loading.

Effect of mulching materials on soil temperature and horticultural attributes in pear (Pyrus pyrifoila (Burm.) Nakai) under humid subtropical climate of Punjab

ABSTRACT- The effect of mulching materials on soil temperature and horticultural attributes in pear under subtropics of northwestern India was studied for years 2018 and 2019. Different mulches such as paddy straw mulch (PSM), white polythene mulch (WPM) and black polythene mulch (BPM) were applied underneath the canopies of ‘Patharnakh’ pear trees during second week of April. The weedy check (control) and manual weeding plots were kept to compare the relative effects of different mulching materials. The observations on soil temperature were noted at weekly interval while the quality parameters of pear fruit were recorded at harvest. Among the time intervals of soil temperatures, the higher soil temperature was observed with the WPM mulch followed by BPM while the minimum soil temperature was recorded with PSM. The WPM treatment showed soil warming effect from 16th to 28th standard meteorological week (SMW) during both the years of investigation. Different mulches significantly influenced the fruit yield and quality attributes of Patharnakh pear. The maximum fruit weight and fruit yield was observed in PSM, while minimum in control as weedy check. The internal quality of pear fruits in terms of total soluble solids was better in PSM and WPM as compared to fruits from control plants. It can be summarized that the readily available soil moisture and optimum soil temperature conditions during fruit development period improves fruit size particularly under PSM and WPM.
 Key words: Soil temperature, mulches, management practices, pear, fruit attributes.

The effect of different consumption rates of the herbicide Harmony 75, VG on the level of stress in soybean plants

Goal. To establish the optimally high efficiency of weed control in soybean crops with a two-time application of the herbicide Harmony 75, VG to relieve stress in crop plants.
 Methods. Field, laboratory, quantitative-weighing, visual, calculation-comparative, mathematical-statistical.
 Results. It was established that a one-time spraying of crops with the herbicide Harmony 75, VG with the maximum consumption rate from the recommended (8.0 g/ ha) could be one of the factors that induced stress in soybean plants, delaying the intensity of photosynthesis and partially inhibiting other physiological processes (chlorophyll content a and b 5 days after spraying decreased (0.8 g/ dm2) compared to the data obtained before spraying (0.9 g/ dm2)). Research has established that two-time spraying of crops with the herbicide Harmony 75, VG at a rate of 5.0 g/ ha, the first — during the phase of the first triple leaf in soybean plants, the second — on the 4th day after the first, with observance of the time interval, ensured seedling control weeds and restrained the formation of vegetative mass, the average indicator of which was significantly lower compared to the average indicator established in the plots of the control version of the experiment, and was 15.7% of it. According to the results of the research, the average seed yield was the closest in value to the average yield of soybean seeds, which was obtained in the control plots of crops, where 4 consecutive manual weeding of crops was carried out during the growing season and the segetal vegetation was completely destroyed (3.31 t/ ha or 91.2%), recorded on the plots of crops with a two-time treatment of Harmony 75, VG with a rate of consumption of 5.0 g/ ha + 200 ml/ ha of PAR Trend 90 (the first treatment during the phase of the first triple leaf in soybean plants, the second treatment at 4 — that day after one).
 Conclusions. Two-time spraying with the herbicide Harmony 75, VG, with a rate of consumption of 5.0 g/ ha + 200 ml/ ha of surfactant Trend 90 (the first time — during the phase of the first triple leaf in soybean plants and the second time — on the 4th day after the first) makes it possible to control the emergence of weeds, restrain the formation of vegetative mass, causes reduced stress in crop plants compared to a one-time introduction of the recommended rate, and ensures a higher yield of soybean seeds.

Effect of preceding rice herbicide residue towards control of weeds and urdbean productivity in rice -Bhendi-urdbean sequence under high rainfall area

Field experiment was conducted at Field Crops Research unit, ICAR- Central Island Research Institute, Bloomsdale, Port Blair during summer season, 2018. To study the preceding rice herbicide residual effect in control of weeds, growth and yield of urdbean in rice-bhendi-urdbean sequence under high rainfall area. At 20 DAS, grassy weeds (48.00 weeds/m2) were predominant species of weeds followed by sedges and broad leaf weeds of 29.67 and 22.67 nos./m2 respectively. Among the irrespective of weed control treatments, at 20 DAS, residual effect of 1.25 kg/ha butachlor at 3 DAP + manual weeding at 40 DAP in rice + two manual weeding on 20 and 40 DAS in both bhendi and urdbean recorded significantly lower grass, sedges, broad leaf weeds population and weed biomass of 11.67, 8.67, 6.67 weeds/m2 and 2.93, 2.02, 1.84 g/m2 respectively. Residual effect of 1.25 kg/ha butachlor applied at 3 DAP along with manual weeding at 40 DAP in rice + two manual weeding on 20 and 40 DAS in both bhendi and urdbean obtained 299 kg/ha higher seed yield as compared to weedy control.

The Effectiveness of Mixing Herbicides and Manual Weed Control on Corn (Zea mays L)

Field trials were conducted in Januay 2021 cropping seasons to evaluate some herbicide mixtures and manual weed control method in the maize production. The experiment consisted of 10 treatments as follows: Metolachlor + atrazine (1.0 + 2.0 kg a.i./ha), metolachlor + atrazine (2.0 + 2.5 kg a.i./ha), metolachlor + atrazine (3.0 + 3.0 kg a.i./ha), pendimethlin + atrazine ( 1.0 + 2.0 kg a.i./ha), pendimethlin + atrazine (2.0 + 2.5 kg a.i./ha), pendimethlin + atrazine (3.0 + 3.0 kg a.i./ha), metolachlor + atrazine (1.0 + 2.0 kg a.i./ha) plus one supplementary hoe weeding (SHW) at 6 weeks after sowing (WAS) and pendimethlin + atrazine (1.0 + 2.0 kg a.i./ha) plus one SHW at 6 WAS, hand weeding at 3 and 6 WAS and a weedy check. These treatments used in randomized complete block design with three replicates. The rsults showed that metolachlor + atrazine and pendimethalin + atrazine at 1.0 + 2.0 kg a.i./ha plus one SHW at 6 WAS significantly reduced weed infestation and gave higher maize grain yield and economic returns. These methods are therefore recommended to farmers as alternative to two hand weeding at 3 and 6 WAS.

Classification of Weeds of Paddy Fields using Deep Learning

Weed management is one of the important tasks in agriculture. Weeds in rice fields are usually managed using three ways - chemical herbicides, mechanical weeders, and manual weeding. Manual weeding becomes a problem when there is a shortage of agricultural laborers. Mechanical weeders are not suitable for direct-seeded rice fields. Chemical herbicides are not advisable especially when farmers do not know about site-specific weed management. Site-specific weed management is using the right herbicide in the right amount. Therefore, this paper investigates computer vision-based deep learning techniques with transfer learning classifying three types of weeds in paddy fields, namely sedges, grasses, and broadleaved weeds so that the right herbicide is recommended to the farmers. This would reduce the broadcast application and the overuse of the herbicides, thereby limiting the negative impact of the chemical herbicides on the environment. This research work shows promising results with an accuracy around 90% and thus encourages the development of digital agriculture.

Efficiency of herbicides for weed control in chickpea and effect of their residues on wheat growth

In order to determine the best time to use and the adequate dose of four herbicides to control weeds in dryland chickpea (Cicer arietinum L.) fields, we performed the present experiment in 4 x 5 m plots. Fourteen treatments were carried out that from 1 to 9 included trifluralin. Treatments 1, 2, and 3 were with increasing doses of trifluralin (480, 720, and 960 g ai ha-1) applied 30 days before planting. Treatments 4, 5, and 6 included increasing doses of trifluralin (480, 720, and 960 g ai ha-1) applied 15 days before planting. Treatments 7, 8 and 9 consisted of increasing doses of trifluralin (480, 720, and 960 g ai ha-1) applied at the time of planting. Treatments 10, 11, and 12 included pyroxasulfone (85 g ai ha-1), flumioxazin (51 g ai ha-1) and imazethapyr (100 g ai ha-1), respectively. These last three treatments were carried out at the time of planting; treatments 13 and 14 were: weed-infested (without weed control) and weed-free (manual weeding during the entire season). Flumioxazin 66% and pyroxasulfone 57% (mean of two samples) reduced weed dry weight compared to uncontrolled treatment. The results showed that the treatments were significantly different for 100-seed weight, biological yield, and seed yield of chickpea. Weed-infested and weed-free plants had the lowest and highest grain yield. Herbicide treatments of flumioxazin, trifluralin 960 g ai ha-1, and pyroxasulfone at planting produced 55%, 44%, and 40% higher grain yield than the weed-infested plots. Also, none of the herbicide treatments reduced chickpea yield and biomass. The herbicide residues had no adverse effect on wheat growth in the next crop season.

Effect of Different Weed Management Practices on Growth and Yield of Direct Seeded Puddled Rice in North Eastern Zones of Tamil Nadu

The field experiment was conducted at Post Graduate Research Institute in Animal sciences Kattupakkam Tamil Nadu, India during Rabi (Oct-Mar) seasons of 2016-17 to study the effect of different weed management techniques in direct seeded puddled rice variety ADT 43. The experiment was laid out with unpaired t test design. The treatment of chemical weed management technique (pre - emergence application of pretilachlor) was compared with two time manual weed management technique (control) in direct seeded puddled rice. Among the weed management techniques, chemical weed management technique significantly influenced the growth and yield characters and yield of direct seeded puddled rice. The maximum plant height, number of tillers /hill, grain yield, straw yield and cost benefit ratio were recorded under chemical weed management technique during Rabi. The lowest grain yield, straw yield were recorded under control treatment.

​Efficacy of Pre and Post-emergence Herbicides for Weed Management in Groundnut

Background: Herbicides are used in agriculture to reduce the density of weeds and improve the crop yield. Pendimethalin 30% EC is widely used pre-emergent herbicide to control annual grasses and certain broad leaf weeds; is no longer effective against established weeds like Cyperus and Commelina benghalensis, Acalypha indica and Phyllanthus spp. that are dominant in groundnut crop. Combination of Pendimethalin 30% and Imazethapyr 2% EC is a broad-spectrum herbicide that controls most broadleaf weeds and some annual grasses. The current study aimed to improve the profitability of farmers by effectively and economically by controlling the targeted weeds. Methods: A field experiment was conducted at Zonal Agricultural and Horticultural Research Station (ZAHRS), Babbur Farm, Hiriyur, Karnataka during Kharif 2018, 2019 and 2020, to study the efficacy of pre and post-emergence herbicides for weed management in groundnut. The trial comprised of nine treatments involving two pre-emergence herbicides (Pendimethalin 38.7 CS 1.0 kg/ha PE and Pendimethalin 30 EC+Imazethapyr 2 EC 1.0 kg/ha PE (ready mix)) alone and in combinations with post-emergence herbicides (quizalofop-p-ethyl 50 g/ha at 15-20 DAS (PoE)), along with pre-emergence herbicides super imposed with hand weeding at 30 DAS and compared with two inter cultural operation at 15 and 30 DAS followed by manual weeding for intra rows and weedy check. Result: The experimental results revealed that, among the different herbicides treatments, the higher net return (Rs. 92,835/ha) and B:C ratio (2.70) were noticed in Pendimethalin 30 EC+Imazethapyr 2 EC 1.0 kg/ha PE (ready mix)+manual weeding at 30 DAS as compared to control plot (Rs. 2620/ha and 0.96, respectively) this has effectively controlled most of the weed flora present in the experimental field.

Влияние метеорологических условий на формирование урожайности сортов сои селекции ВНИИ сои

Abstract. The purpose is to study correlation dependence of soybean varieties yield on hydrothermal conditions of the southern zone of the Amur region. Methods. The subject of research are local recognized standard soybean varieties – Lidiya, Dauriya, and Alena. The experimental part of the work was carried out in 2017–2021 on the experimental field of the Soybean Breeding and Genetics Laboratory of the Federal State Budget Scientific Institution Federal Research Center All-Russian Scientific Research Institute of Soybean (FSBSI FRC ARSRIS). The varieties were studied in the nursery of competitive variety testing. Sowing was carried out in triplicate by the method of randomized repetitions (blocks) in the period from May 19 to May 21 using a SN-P-16 seeder. The plot area is 40.5 m2. During the growing season, cultivation, manual weeding, phenological observations and visual assessments were carried out. The plots were harvested by continuous threshing with a Sampo 130 combine. The yield of varieties was determined in terms of standard moisture content (14 %). Results. In the course of the yield data analysis of varieties depending on weather conditions it was found that 2019 and 2020 were excessively wet (HTF – 2.6; 2.4), optimum conditions developed in 2017 (HTF – 1.7). The highest average varietal yield (26.5) over the years of research was noted in 2017, the lowest (23.4 c/ha) – in adverse meteorological conditions of 2018, due to drought period of the early plant growth and heavy storm rainfall afterwards. It was found in the course of research that formation of the Lidiya soybean variety yield is mainly influenced by the effective heat sum during periods of sprouting – flowering and flowering – ripening (r = 0.51 and –0.53). The productivity of the Dauriya variety is more dependent on the air temperature (r = –0.61) and total precipitation, and HTF of flowering – ripening periods (r = 0.62; 0.67). The Alena soybean variety showed a fairly close correlation dependence of the productivity on the effective heat sum of the periods of dropping – sprouting and flowering – ripening (r = –0.87 and –0.68), and the amount of precipitation and HTF of the period sprouting – flowering (r = –0.64 and –0.60 respectively). Scientific novelty. Special aspects of meteorological effects on the yield of soybean varieties of various ripeness groups have been established; the correlation between them have been determined. It has been found that all studied varieties are highly adapted to changing weather and climatic conditions of the Amur Region.