Weed Interference and Growth Performances in Soybean ( Glycine max (L.) Merr.), as affected by Weed Density and Types of Weed

: The aim of this study was to evaluate of the density for four weeds on growth inhibition against soybean ( Glycine max ) (Chiang Mai 2 variety). The experiment were interfered with four weeds namely wild poinsettia ( Euphorbia heterophylla ), eclipta ( Eclipta prostrata ), slender amaranth ( Amaranthus viridis ) and spiny amaranth ( Amaranthus spinosus ) against soybean ( G. max ). The number of four weeds interfered with soybean planting divided into five treatments; 0 (control treatment) 4 8 12 and 16 plants/m 2 . Stem height, leaf area, fresh weight of aboveground part and dry weight of aboveground part of soybean were measured at 28 days after planting. The results showed that the increase of number of four weeds resulted in the increase of inhibition of all growth performance in soybean. The planting of soybean interfered with the weeds for 16 plants/m 2 exhibited that the maximum of inhibitory degree (52.61%) followed by the planting of soybean interfered with the weeds for 12 8 and 4 plants/m 2 by 40.04, 25.94 and 13.08%, respectively. The planting of soybean interfered with spiny amaranth ( A. spinosus ) exhibited that the highest of inhibitory degree (35.41%), followed by the planting of soybean interfered with eclipta ( E. prostrata ), wild poinsettia ( E. heterophylla ) and slender amaranth ( A. viridis ) showed the inhibitory degree for 34.35, 31.65 and 30.27%, respectively. This result presented the effects of density of weeds against soybean on growth parameters (stem height, leaf area, fresh weight of aboveground part and dry weight of aboveground part) as well as suggested that the planting of soybean should be the planting of soybean were not interfered with different weed density in order to the minimization of weed competition as well as the optimum method for weed arrangement.


Introduction
Soybean (Glycine max L. Merr.) is the economic legume crop for three issues of utilization included food of human (Matsuo et al., 2018) feed for animal (Ferdous et al., 2017) and industrial application (Korres et al., 2020) and soybean contains abundant of protein and oil content (Das et al., 2014) and richs of mineral nutrients and vitamins (Matsuo et al., 2018). Soybean is the most important of legume crops, seeds of soybean comprise three groups of biochemical substance namely protein (36%) carbohydrate (30%) and oils (20%) (Ferdous et al., 2017). Seeds of soybean were applied more than 50% of the total production of legume crops as oil crops application in the world (Matsuo et al., 2018).
Weeds is the economic pest of the agricultural fields and soybean cultivation as well as weeds showed the competition and interfered with the economic crops planting and soybean cultivation for three factor competition (water light and nutrition) for growth and development (Reis and Vivain, 2011). Shrestha et al. (2010) summarized that the disadvantage of weed infestation against the crops planting because the potential of the weed competition minimized of some factors (water, light and nutrition) on growth and yield of the crops planting.
The accumulation of the weed density in crop planting showed the growth retardation as well as the minimization of yield is more harmful than the reduction of the weed density (Agostinetto et al., 2017). For the soybean planting and economic field crops interfered with weeds competition showed the injury of some characters of crops and soybean planting included reduction of the growth characters (Keramati et al., 2008), damage of the yield components (Du et al., 2019) and decrease of the yields (Korres et al., 2020).
Weed interference exhibited that the damage of the growth character, minimization of the yield components and decrese of the yields charaters of the economic crops (Chauhan, 2011) For examples, Dhaker et al. (2010) inferred that the damage of the yield components and yield characters (pod length, pod weight and seed yield) of soybean (G. max) planting resulted from the weed interference namely Trianathema portulacastrum, Commelina benghalensis, Amaranthus spinosus, Digera arvensis and Parthanium hysterophorus. Jeschke et al. (2011) concluded that the yield loss of soybean (G. max) caused by the competition of two weed inferference namely giant foxtail (Setaria faberi) and yellow foxtail (Setaria pumila). Kavurmaci et al. (2010) predicated that the growth loss and yield damage in term of plant height, number of pods per plant, number of seeds per pod, seed weight and seed yield against faba bean (Vicia faba) resulted from weed competition namely avena sterilis, Lolium multiflorum, Chenopodium album, Amaranthus retroflexus, Convolvulus arvensis and Sinapsis arvensis. Vollmann et al. (2010) summarized that the weed infestation treatments noted that the grain yield loss of soybean (G. max) is more destroyed than the weed free control. Bukun (2011)  hypogoea) cultivation interfered with some weed (eclipta (Eclipta prostrata) exhibited that the loss of growth characters is more injured than the control treatment (no weed competition). Belel et al. (2011) abstracted that the weed competition treatment for 2 4 and 6 weeks after planting against sweet pepper (Capsicum annuum) showed the damage of the growth and yield component (fruit length, fruit diameter and fruit yield) is more destroyed than the weed free duration (no weed competition). Omoigui et al. (2012) noted that the weed infestation treatments (Striga gesnerioides and Alectra vogeli) against cowpea (Vigna unguiculata) showed the damage of growth and yield in term of pod per plant, seed weight and seed yield is more devastating than the control treatment (no weed infestation). Galon et al. (2016) comprehended that the number of weed competition (Bidens pilosa) of 60 plants/m 2 showed the highest of the productivity loss percentages against black bean (Phaseolus vulgaris) for 45%, while the number of weed competition (B. pilosa) of 10 plants/m 2 presented that the lowest of the productivity loss percentages against black bean (P. vulgaris) for 30% as well as the control treatment (without infestation of weed) showed the productivity loss percentages against black bean for 0%.
Besides, Du et al. (2019) inferred that the effect of the number of purple nutsedge (Cyperus rotundus) against peanut (A. hypogoea), the mumber of purple nutsedge (C. rotundus) of 150 plants/m 2 showed the minimum of peanut yield for 1.2 ton/ha -1 , while the mumber of purple nutsedge (C. rotundus) of 10 plants/m 2 showed the maximum of peanut yield for 2.6 ton/ha -1 and the increase of the number of weed infestation resulted in the reduction of the peanut seed yield.
In the same way, Peer et al. (2013) noted that the weed infestation of soybean cultivation minimized on the growth of soybean and reduced on yield of soybean compared with the control treatment (no weed infestation). Besides, Korres et al. (2020) exhibited that the weed infestation treatments (soybean planting interfered with Amaranthus palmeri showed the seed yield loss of soybean (G. max) is more shabby than the weed free control (soybean planting without infestation of A. palmeri).
An inadequate data and incomplete information of the detriment of the growth charateristics (stem height, leaf area, fresh weight of aboveground part and dry weight of aboveground part) of soybean (G. max) resulted from weed interference for four weeds namely wild poinsettia (E. heterophylla), eclipta (E. prostrata), slender amaranth (A. viridis) and spiny amaranth (A. spinosus).
The objective of this research was to study of the weed interference for four weeds namely wild poinsettia (E. heterophylla), eclipta (E. prostrata), slender amaranth (A. viridis) and spiny amaranth (A. spinosus) against soybean (G. max). It is predicated that the data may help to selection the weed species as the aggressive weed at the first time for weed management in soybean planting, consequence the selection the weed species as the non-aggressive weed at the second time for weed management in soybean planting.

The tested plants and samples
The soybean seeds were tested in this experiments as the local variety (Chiang mai 2 variety). The four weed species in this study namely wild poinsettia (E. heterophylla), eclipta (E. prostrata), slender amaranth (A. viridis) and spiny amaranth (A. spinosus) were collected from the Agricultural fields for three locations (Bangban, Wangnoi, and Uthai) in Phranakhon Si Ayutthaya Province (14 ๐ 21 / N, 100 ๐ 34 / E), Thailand, during January-May, in 2018.
The data of four weed species are shown in Table 1. Table 1 The data of Family, scientific name, types of weeds and the score of loss to soybean cultivation of each weed.

The soybean growth evaluation
The soybean growth evaluation were recorded at 28 days after planting for four characters namely stem height, leaf area, fresh weight of aboveground part and dry weight of aboveground part. For the stem height test, the plant height were measured from the base of the stem to the apex of the stem at 28 days after planting.
The leaf area character were measured at 28 days after planting for two types character of this leaves included leaf width and length length and calculated for leaf area (LA; cm 2 ) from the formula as follows ; LA = (AxB) Where A is the data of leaf width (cm.) were measured from the leaf margin one side to the leaf margin other side and B is the data of leaf length (cm.) were measured from the leaf base to the leaf apex.
The growth performances in term of fresh weight of aboveground part and dry weight of aboveground part were measured at 28 days after planting and tested followed by the methods of AOSA (2002).
The soybean growth performances were measured at 28 days after planting for four charaters (stem height, leaf area, fresh weight of aboveground part and dry weight of aboveground part) were taken on the growth inhibition (M) with respect to the control treament (no weed interfered with soybean planting) was calculated from the formula as follows; Where A is the growth parameters (stem height, leaf area, fresh weight of aboveground part and dry weight of aboveground part) of the control treament (no weed interfered with soybean planting) and B is the growth parameters (stem height, leaf area, fresh weight of aboveground part and dry weight of aboveground part) of the treatments were interfered with the four weeds at different density for 4 8 12 and 16 plants/ m 2 namely wild poinsettia (E. heterophylla), eclipta (E. prostrata), slender amaranth (A. viridis) and spiny amaranth (A. spinosus).

Statistical analysis
All experiments were tested for four replications. Data of four characteristics (inhibition of stem height, inhibition of leaf area, inhibition of fresh weight of aboveground part and inhibition of dry weight of aboveground part of soybean were measured at 28 th days after planting) were subjected to analysis using Duncan , s Multiple Range Tests (DMRT).

Results and discussion 3.1 Impaction of density of wild poinsettia (E. heterophylla) on growth performances against soybean
The density of wild poinsettia (E. heterophylla) at different treatments showed the inhibition of stem height, leaf area, fresh weight of aboveground part and dry weight of aboveground part ranged from 22.36% to 62.34% inhibition. The density of wild poinsettia for 4 plants/m 2 demonstrated that the lowest of inhibition of stem hight character against soybean for 22.36% inhibition ( Table 2). The density of wild poinsettia for 16 plants/m 2 noted that the peakest of inhibition of stem hight character against soybean for 62.34 % inhibition. The density of wild poinsettia for 8 and 12 plants/m 2 against soybean exhibited that the degree of inhibition of stem height for 31.06 and 45.69 % inhibition, respectively ( Table  2). The data of the damage of the stem height charater against soybean caused by wild poinsettia competition exhibited inconformity with the researchs of Mishra et al. (2003) who found that the the decrease of the growth performance of soybean resulted from the Euphorbia sp. interference condidion as well as Adeluis et al. (2006) who showed tha the damage of the growth performance in term of stem hight of soybean caused by the wild poinsettia competition.  (Table 2). This data showed that the inconformity with the other researchs of Rezvani et al. (2012) who exhibited that the damage of the growth character against soybean planting resulted from the increasing of the weed competition of soybean planting. Trezzi et al. (2013) who reported that the harm of growth character in case of dry matter of leaves and dry matter of stems against soybean caused by weed competition (horseweed; Conyza banariensis).

Impaction of density of eclipta (E. prostrata) on growth performances against soybean
The density of eclipta (E. prostrata) for 16 plants/m 2 showed that the highest of the inhibition on growth in term of stem height against soybean for 64.15% inhibition. The density of eclipta for 4 plants/m 2 exhibited that the lowest of inhibition of stem height against soybean by 9.76 % inhibition ( Table 3). The data of weed competition against soybean showed the injury of growth performance in term of stem height of soybean caused by eclipta (E.  (Table 3). These data presented that the weed competition of eclipta against soybean showed that inconformity with the working of The density of eclipta at different treatments affected that the growth parameter in term of fresh weight of above ground part against soybean, the population of eclipta for 16 plants/m 2 showed that the peakest of inhibition incase of fresh weight of aboveground part (49.68% inhibition). The population of eclipta for 4 plants/m 2 exhibited that the lowest of inhibition (7.45% inhibition) in case of fresh weight of above ground part against soybean (Table 3) For the loss of dry weight of above ground part against soybean interfered with different eclipta density, the density of eclipta for 16 plants/m 2 presented that the maximum of inhibition (54.67%inhibition) followed by the density of eclipta by 12 and 8 plants/m 2 for 46.78 and 31.23 %inhibition, respectively. The density of eclipta for 4 plants/m 2 exhibited that the lowest of inhibition (13.64% inhibition) ( Table 3). The data of growth inhibition of soybean caused by eclipta competition that corroborate the working of Ferdous et al. (2017) who showed that the eclipta infestation of soybean planting resulted in the loss of the growth performance in term of dry weight plants against soybean. Besides, Pagnoncelli et al. (2017) who showed that the impaction of the density of weed competition on some growth parameters (stem height, leaf area, fresh stem mass and dry stem mass) against soybean.

Impaction of density of slender amaranth (A. viridis) on growth performances against soybean
The population of slender amaranth (A. viridis) for 16 plants/m 2 showed that the highest of inhibition interm of stem hight (74.52% inhibition) against soybean followed by the population of slender amaranth by 12 and 8 plants/m 2 for 51.12 and 34.75 % inhibition, respectively. The population of slender amaranth by 4 plants/m 2 exhibited that the lowest of inhibition incase of stem height against soybean ( Table 4). The data of the damage of growth parameter of soybean in case of stem height interfered with slender amaranth showed inconformity with the data of the weed competition against soybean of Imoloame (2014) who comprehended that the effect of the weed competition in soybean cultivation resulted in the loss of the growth character in term of plant height against soybean.
The density of slender amaranth (A. viridis) at different of density treatments showed the inhibition of leaf area character against soybean for 11.23-45.29% inhibition ( Table 4). The density of slender amaranth for 16 plants/m 2 exhibited that the peakest of inhibition of leaf area against soybean for 45.29% inhibition. The density of slender amaranth for 4 plants/m 2 presented that the lowest of leaf area against by 11.23% inhibition. The raising of the population of slender amaranth resulted in the increase of inhibition of leaf area character against soybean. These data confirm the finding of the research by Pagnoncelli et al. (2017) who showed that the impaction of the density of morning glory infestation of soybean planting inhibited of some growth parameters in case of leaf area against soybean.
The increase of density of slender amaranth (A. viridis) resulted in the increase of inhibitory degree of growth parameter in term of fresh weight of above ground part against soybean. The density of slender amaranth for 16 plants/m 2 showed that the maximum of the inhibition (35.69% inhibition) ( Table 4). The density of slender amaranth for 4 plants/m 2 noted that the lowest of the inhibition (8.96% inhibition). From these study, the results confirm the finding of Pagnoncelli et al. (2017) who concluded that the impaction of the density of morning glory infestation of soybean planting presented that the loss of some growth parameters in term of fresh stem mass and dry stem mass against soybean.
The population of slender amaranth at different density (4 8 12 and 16 plants/m 2 ) presented that the inhibition of growth character in case of dry weight of above ground part against soybean ranged from 13.26% to 49.96% inhibition ( Table 4). The

Impaction of density of spiny amaranth (A. spinosus) on growth performances against soybean
The population of spiny amaranth (A. spinosus) for 16 plants/m 2 demonstrated that the highest of inhibition of stem hight against soybean for 81.45% ihhibition. The population of spiny amaranth by 4 plants/m 2 noted that the lowest of inhibition of stem height for 25.63% inhibition ( Table 5). The increase of the density of spiny amaranth showed that the raising of inhibition of growth character incase of leaf area against soybean. The density of spiny amaranth by 4 plants/m 2 presented that the lowest of the inhibition (14.56% inhibition), while the density of spiny amaranth by 16 plants/m 2 showed that the peakest of inhibition (47.18% inhibition) ( Table 5). These data from the study of spiny amaranth interfered with the soybean planting showed the incoformity with the finding by Aluko et al. (2012) and Amaregouda et al. (2013).
The raising of the population of spiny amaranth resulted in the increasing of the inhibition of two growth charaters in term of fresh weight aboveground part and dry weight aboveground part ( Table 5). The population of spiny amaranth by 16 plants/m 2 showed that the highest of inhibition of fresh weight aboveground part and inhibition of dry weight aboveground part for 42.26 and 51.19 % inhibition, respectively. while, the population of spiny amaranth by 4 plants/m 2 noted that the lowest of inhibition of fresh weight aboveground part and inhibition of dry weight aboveground part for 6.96 and 17.84 % inhibition, respectively. The data from the study showed the agreement with the finding works of Ferdous et al. (2017).

The effects of different density of four weed species interfered with soybean planting on growth performance against soybean
The cumulative of the population of four weed species (wild poinsettia (E. heterophylla), eclipta (E. prostrata), slender amaranth (A. viridis) and spiny amaranth (A. spinosus)) showed that the increase of the inhibitory degree on growth performances (stem height, leaf area, fresh weight aboveground part and dry weight aboveground part) against soybean ( Table  6).
The population of the weed competition for 16 plants/m 2 noted that the peakest of the inhibition of growth performance for 52.41% inhibition against soybean, followed by the population of weed competition by 12 Peer et al. (2013) who demonstrated that the weed infestation of soybean cultivation showed the loss of growth and yield against soybean is more ricketly than the weed free treatment. Besides, Amaregouda et al. (2013) who described that the soybean planting interfered with weed competition showed the loss of growth and yield characters in case of leaf area, total drymatter, pod weight and seed yield against soybean is more destroyed than the control treatment (weed free treatment).
In addition, the different types of the weeds for testing showed the different degree of the inhibition for weed interference against soybean planting. The spiny amaranth (A. spinosus) interfered with soybean planting exhibited that the highest of inhibitory degree for 35.41% inhibition, followed by the eclipta (E. prostrata) and wild poinsettia (E. heterophylla) for 34.35 and 31.65 % inhibition, respectively. The slender amaranth (A. viridis) interfered with soybean planting showed the lowest of inhibitory degree for 30.27% inhibition (Table 6). These results showed that the difference of weed species infestation resulted in the difference of the damage of growth performances against soybean. The spiny amaranth (A. spinosus) competition showed the highest of the damage of growth performances against soybean, while the slender amaranth (A. viridis) competition showed the lowest of the damage of growth performances against soybean.
The data from these study demonstrated that inconformity with the researchs of Ferdous et al. The population of weed competition as high levels competition treatment (16 plants/m 2 ) presented that the maximum of the inhibition (52.61% inhibition) of growth characters against soybean planting, while the population of weed competition as low levels competition treatment (4 plants/m 2 ) exhibited that the minimum of the inhibition (13.08 % inhibition) of growth characters against soybean planting (Table 6).
From these study, the population of weed competition as high levels competition treatment (16 plants/m 2 ) showed the loss of growth performances against soybean is more disruptive than the population of weed competition as low levels competition treatment (4 plants/m 2 ). The results corroborate that the researchs of Das et al. (2014) who aggregated that the weed interference of soybean planting by 25 50 100 150 and 200 plants/m 2 showed the loss of seed yield against soybean by 10-41%, the weed interference of soybean planting by 200 plants/m 2 exhibited that the peakest of the loss of seed yield for 41%, while the weed interference of soybean planting by 25 plants/m 2 presented that the lowest of the loss of seed yield for 10%.
Furthermores, Du et al. (2019) who discovered that the weed interference of peanut planting by 10 20 40 80 120 and 160 plants/m 2 showed the loss of seed yield against peanut ranged from 4% to 49%, the weed interference of peanut planting by 160 plants/m 2 displayed that the highest of the loss of seed yield for 49%, while the weed interference of peanut planting by 10 plants/m 2 revealed that the lowest of the loss of seed yield for 4%.
The weed competition showed the damage of the growth performances against soybean that inconformity with the researchs of Hazra et al. (2011) who noted that the horse purslane (Trianthema portulacastrum) competition of soybean cultivation resulted in the loss of growth and yield against soybean is more destructive thant the control treatment (no weed competition) as well as Trezzi et al. (2013) who showed that the horseweed (Conyza bonariensis) competition of soybean planting resulted in the loss of growth appearance incase of leaf area, branch per plant and dry matter of leaves against soybean is more dilapidated than the control treatment.
In the same way, Agostinetto et al. (2017) who reported that the soybean planting interfered with hairy fleabane infestation showed the loss of growth and yield against soybean is more harmful than the soybean planting alone (no weed interference).
The data from this research is the invaluable data of the weed interference study against soybean planting. The selection of the weed control as the highest of the inhibitory degree of some weed (aggrassive weed) at the first time in weed mananement included the spiny amaranth (A. spinosus) competition (35.41% inhibition), then the selection of the weed control as the lowest of the inhibitory degree of some weed (non-aggrassive weed) at the second time in weed management included the slender amaranth (A. viridis) competition (30.27% inhibition).
These finding inferred that qualitative data of the weed interference for four weed species (wild poinsettia (E. hyterophylla), eclipta (E. prostrata), slender amaranth (A. viridis) and spiny amaranth (A. spinosus) on some growth performances (stem height, leaf area, fresh weight of aboveground part and dry weight of aboveground part) of soybean.
It is the comprehensive information of weed interference in soybean cultivation as well as the applicatiom of the data of weed competition of these finding for selection method of the best control for weed management of soybean planting.

Conclusion
This research presented the effects of different density (0 4 8 12 and 16 plants/m 2 ) for four weed species (wild poinsettia (E. hyterophylla), eclipta (E. prostrata), slender amaranth (A. viridis) and spiny amaranth (A. spinosus)) on growth characteristics against soybean (G. max). The increase of number of four weeds resulted in the increase of inhibition of all growth performances (stem height, leaf area, fresh weight of aboveground part and dry weight of aboveground part) against soybean.
The planting of soybean interfered with the weeds for 16 plants/m 2 exhibited that the maximum of inhibitory degree (52.61%) followed by the planting of soybean interfered with the weeds at 12 8 and 4 plants/m 2 for 40.04, 25.94 and 13.08%, respectively. The data of the damage of the the growth performance against soybean planting showed the difference of inhibitory degree depending on the type of weed species. The planting of soybean interfered with spiny amaranth (A. spinosus)) exhibited that the highest of inhibitory degree (35.41%), followed by the planting of soybean interfered with eclipta (E. prostrata), wild poinsettia (E. hyterophylla) and slender amaranth (A. viridis) demonstrated the inhibitory degree for 34.35, 31.65 and 30.27%, respectively.
This result presented the effects of density of weeds against soybean on growth parameters (stem height, leaf area, fresh weight of aboveground part and dry weight of aboveground part) as well as suggested that planting of soybean should be the planting of soybean were not interfered with different weed density in order to weed arrangement.
These finding showed that comprehensive data of the weed interference of four weed species (wild poinsettia (E. hyterophylla), eclipta (E. prostrata), slender amaranth (A. viridis) and spiny amaranth (A. spinosus) on growth characteristics against soybean (G. max). It is the newest information as weed competition in soybean planting had exploited for the optimum selection method of the best control for weed administration. Values with different letter showed significant difference (p<0.05) as determined by Duncan , s Muntiple Range Test (DMRT).  Values with different letter showed significant difference (p<0.05) as determined by Duncan , s Muntiple Range Test (DMRT). Values with different letter showed significant difference (p<0.05) as determined by Duncan , s Muntiple Range Test (DMRT).