Growth and Dry Matter Accumulation of Okra (Abelmoschus esculentus L.) as Influenced by Different Plating Pattern Under Okra-Cowpea (Vigna unguiculata L.) Intercropping

Compared to sole cropping, intercropping efficiently use the existing resources which ultimately lead to improved plant growth and dry matter accumulation. Economically sustainable intercropping system mainly depends on adaptation of planting pattern and selection of compatible crops. The experiment was carried out at the Crop Farm of Eastern University, Sri Lanka in 2018 to investigate the growth and dry matter accumulation in okra (Abelmoschus esculentus L.) as influenced by different planting patterns under okra-cowpea (Vigna unguiculata L. Walp) intercropping in sandy regosol. The experiment was laid out in a Randomized Complete Block Design (RCBD). Treatments were okra as a sole crop (T1), cowpea as a sole crop (T2), alternative planting of okra and cowpea (T3), 60/150 cm paired row planting of okra with two rows and three rows of cowpea in between paired rows (T4 and T5) and 75/120 cm paired row planting of okra with two rows and three rows of cowpea in between paired rows (T6 and T7). Plant height, root length, fresh and dry weights of plant, leaf area, leaf area index, canopy width and cumulative yield of okra were higher in T5, while chlorophyll content showed no significant difference (P>0.05) with different planting patterns. The present study concluded that 60/150 cm paired row planting of okra with three rows of cowpea in between paired rows (T5) would be the most suitable planting system in sandy regosol to achieve better growth and dry matter in okra. Introduction Okra (Abelmoschus esculentus L.) is one of the most economically important vegetable crops belonging to the family Malvaceae. It provides essential nutrients for human. Eastern region in Sri Lanka is a warm region and much suitable for the growth and development of okra. However, low yield resulting from poor nutrient status of the soil has been identified as one of the major factors limiting okra production [1]. Also Nitrogen and Phosphorus are most required important elements in fruit, seed and quality development of okra [2]. With the continual increase of the world population, the increase in food production should be taken into consideration in a comprehensive manner. As well, urbanization may cause to limit the agricultural processes by reducing the land area for cultivation. Therefore, at present most farmers in developing countries used to increase the crop yield and food production by increasing production per unit land area. Intercropping with legumes is the most appropriate for suggesting as a solution for all these problems. Intercropping is the cultivation of two or more crops simultaneously in the same land that provides the possibility of yield benefit in accordance with sole cropping [3]. Intercropping can be performed with different planting patterns, while facilitating the use of environmental resources such as light, moisture and space efficiently to accumulate more dry matter and enhance the growth. Intercropping systems mostly influence to efficient use of soil nitrogen [4]. In this system, one of the crops would be a legume that has the ability to fix atmospheric nitrogen. Intercropping okra with cowpea (Vigna unguiculata L.) can improve N-use efficiency because the two crops use different Npools and cowpea can release biologically fixed N to okra. Thus, okra need less N to produce its best yield. Absorption of mineral N by the non-legume reduces soil N pool, thus stimulating N2 fixation Journal of Horticulture and Plant Research Submitted: 2019-01-01 ISSN: 2624-814X, Vol. 7, pp 81-96 Revised: 2019-03-12 doi:10.18052/www.scipress.com/JHPR.7.81 Accepted: 2019-04-11 2019 SciPress Ltd, Switzerland Online: 2019-08-28 SciPress applies the CC-BY 4.0 license to works we publish: https://creativecommons.org/licenses/by/4.0/ by legume [5]. As well, in intercropping systems, more efficient utilization of growth resources may lead to yield advantages and increased stability compared to sole cropping [6]. Intercropping okra with several crops has been reported by several scientists, but there seem to be no sufficient information on growth and dry matter accumulation of okra as influenced by okra cowpea intercropping studies in Sri Lanka. Therefore, this study was aimed to investigate the growth and dry matter accumulation of okra as influenced by different planting patterns under okra-cowpea intercropping in sandy regosol. Methodology Experimental site and climate The field experiment was conducted at the crop farm, Eastern University, Sri Lanka, in 2018 to investigate the growth and dry matter accumulation of okra as influenced by different planting patterns under okra-cowpea intercropping in sandy regosol. Experimental location is located in the latitude of 70 430 and the longitude of 810 42E. It belongs to the agro ecological region of low country dry zone in Sri Lanka. The mean annual rainfall of the crop farm ranges from 1400 mm to 1680 mm and temperature varies from 300 C to 320 C. The soil type in the experimental site is sandy regosol. The proceeding crop in the experimental site was knol khol. Experimental design and treatments This experiment was carried out using Randomized Complete Block Design (RCBD) with seven treatments. T1: Okra as a sole crop with the spacing of 90 cm × 90 cm (Fig. 1), T2: Cowpea as a sole crop with the spacing of 30 cm × 15 cm (Fig. 2), T3: Alternative planting of okra and cowpea (Fig. 3), T4: 60/150 cm paired row planting of okra with two rows of cowpea in between paired rows (Fig. 4), T5: 60/150 cm paired row planting of okra and three rows of cowpea in between paired rows (Fig. 5), T6: 75/120 cm paired row planting of okra and two rows of cowpea in between paired rows (Fig. 6), T7: 75/120 cm paired row planting of okra and three rows of cowpea in between paired rows (Fig. 7). Figure 1: Sole okra with spacing 90 cm X 60 cm Figure 2: Sole cowpea with spacing 30 cm X 15 cm 82 JHPR Volume 7


Introduction
Okra (Abelmoschus esculentus L.) is one of the most economically important vegetable crops belonging to the family Malvaceae. It provides essential nutrients for human. Eastern region in Sri Lanka is a warm region and much suitable for the growth and development of okra. However, low yield resulting from poor nutrient status of the soil has been identified as one of the major factors limiting okra production [1]. Also Nitrogen and Phosphorus are most required important elements in fruit, seed and quality development of okra [2].
With the continual increase of the world population, the increase in food production should be taken into consideration in a comprehensive manner. As well, urbanization may cause to limit the agricultural processes by reducing the land area for cultivation. Therefore, at present most farmers in developing countries used to increase the crop yield and food production by increasing production per unit land area. Intercropping with legumes is the most appropriate for suggesting as a solution for all these problems.
Intercropping is the cultivation of two or more crops simultaneously in the same land that provides the possibility of yield benefit in accordance with sole cropping [3]. Intercropping can be performed with different planting patterns, while facilitating the use of environmental resources such as light, moisture and space efficiently to accumulate more dry matter and enhance the growth. Intercropping systems mostly influence to efficient use of soil nitrogen [4]. In this system, one of the crops would be a legume that has the ability to fix atmospheric nitrogen. Intercropping okra with cowpea (Vigna unguiculata L.) can improve N-use efficiency because the two crops use different Npools and cowpea can release biologically fixed N to okra. Thus, okra need less N to produce its best yield. Absorption of mineral N by the non-legume reduces soil N pool, thus stimulating N2 fixation by legume [5]. As well, in intercropping systems, more efficient utilization of growth resources may lead to yield advantages and increased stability compared to sole cropping [6].
Intercropping okra with several crops has been reported by several scientists, but there seem to be no sufficient information on growth and dry matter accumulation of okra as influenced by okracowpea intercropping studies in Sri Lanka. Therefore, this study was aimed to investigate the growth and dry matter accumulation of okra as influenced by different planting patterns under okra-cowpea intercropping in sandy regosol.

Experimental site and climate
The field experiment was conducted at the crop farm, Eastern University, Sri Lanka, in 2018 to investigate the growth and dry matter accumulation of okra as influenced by different planting patterns under okra-cowpea intercropping in sandy regosol. Experimental location is located in the latitude of 7 0 43 0 and the longitude of 81 0 42E. It belongs to the agro ecological region of low country dry zone in Sri Lanka. The mean annual rainfall of the crop farm ranges from 1400 mm to 1680 mm and temperature varies from 30 0 C to 32 0 C. The soil type in the experimental site is sandy regosol. The proceeding crop in the experimental site was knol khol.

Experimental design and treatments
This experiment was carried out using Randomized Complete Block Design (RCBD) with seven treatments. T1: Okra as a sole crop with the spacing of 90 cm × 90 cm (Fig. 1), T2: Cowpea as a sole crop with the spacing of 30 cm × 15 cm (Fig. 2), T3: Alternative planting of okra and cowpea (Fig. 3), T4: 60/150 cm paired row planting of okra with two rows of cowpea in between paired rows (Fig. 4), T5: 60/150 cm paired row planting of okra and three rows of cowpea in between paired rows (Fig. 5), T6: 75/120 cm paired row planting of okra and two rows of cowpea in between paired rows (Fig. 6), T7: 75/120 cm paired row planting of okra and three rows of cowpea in between paired rows (Fig. 7).

Varieties used as planting materials
Okra variety Haritha and cowpea variety Waruni were used as planting materials and the seeds were collected from the seed processing unit of Eastern University, Sri Lanka. Okra seeds were soaked overnight before planting. Okra variety Haritha bear medium sized dark green fruits which is suitable for all agro climatic region of Sri Lanka. Its stem has strong anthocyanin pigmentation and Haritha is tolerant to Yellow Vein Mosaic Virus. Cowpea variety Waruni exhibits erect and determinate growth while flowering in about 40 days after planting. It bears long dark green pods. Seeds are medium in size and reddish brown. It gives an average yield 1650kg/ha.

Field establishment
Land was harrowed and levelled. Cow dung and basal fertilizers were mixed to the land before planting as per recommendation of Department of Agriculture, Sri Lanka. Size of each plot was 4 m × 3 m. Each treatment replicated four times. The total number of plots was 28. A spacing of 0.5 m separated the plot from each other and a space of 1 m wide separated the blocks from each other. 3-4 seeds were planted per one hill. Number of plants per each plot was 28.

Data collection
Three stands of okra were selected from each plot at each time. Data were collected by destructive sampling method. Data collection was commenced two weeks after planting and continued at two weeks interval. Growth parameters such as plant height, root length, number of leaves and branches, leaf area, leaf area index, fresh and dry weights of total plant, shoot, leaves and root and yield parameters such as cumulative yield and 100 seed weight of sun dried seeds were taken. Area Harvest Equivalent Ratio (AHER) was calculated as a productivity index by using the following Equation derived by [7].
where Oyi and Cyi = Yield of okra and cowpea in intercropping; Oys and Cys = Yield of okra and cowpea in sole cropping; n = number of harvest.

Statistical analysis
Statistical software such as SAS and Minitab were used for data analysis. Parametric and nonparametric analysis were done depend on type of data.

Plant height
There was no significant difference (P>0.05) in plant height at 2 nd and 4 th week after planting (WAP). But, a significant difference (P<0.05) was noted at 6 th and 8 th WAP is shown in Fig. 8. Tallest okra plant was recorded in T5 (47.54 cm), while shortest plant were recorded in T1 (29.54 cm) at 6 th WAP. Average plant height ranged from 51.69 cm (T5) to 39.16 cm (T1) at 8 th WAP. There was no significant difference (P>0.05) in plant height among T3, T4, T6 and T7. Okra in intercropping has a chance to get more nitrogen for the growth, as nitrogen is much essential for the vegetative growth may be the reason for taller plant in intercropping compared with monocropping. Plant height of okra was high in intercropping with cowpea than in sole cropping [8]. In contrast, [9] revealed that plant height of sole cropping of okra gave higher values than intercropping. Spacing between rows in paired was narrower than monocropping may be the reason for taller plant in intercropping to utilize the solar radiation effectively. This result is agreeable with [10] that plant height of okra increased with the reduction of row spacing in intercropping with groundnut. Similar finding was cited by [11] that, superior plant heights of okra were produced in intercropping systems with maize over sole cropping of okra.

Root length
There were no significant differences (P>0.05) in root length at 2 nd and 4 th WAP. However, significant differences (P<0.05) were obtained in 6 th week and 8 th WAP is shown in Table 1. Longest root of 17.04 cm were obtained in T5, while shortest of 11.21 cm was noted in T7 at 6 th WAP. But at 8 th WAP longest roots were recorded in T1 (23.71 cm). These results are in line with the work of [9] that root length of okra was high in sole cropping than in intercropped with cowpea. On the other hand, [8] noted that, root length was high in okra cowpea intercropping in 1:1 than sole cropping.

Number of leaves per plant
There was no significant difference (P>0.05) among tested treatments in number of leaves at 2 nd and 4 th WAP was confirmed with P values of 0.156, and 0.323 and chi square values of 8.00 and 5.83 is shown in Table 2. Recorded number of leaves per plant at weekly interval suggest that differences of cropping system which have been significantly affected the number of leaves at 6 th and 8 th weeks after planting is confirmed with P values of 0.004, 0.000 and chi square values of 17.02, 29.21. More number of leaves per plant was noted in T1 at 6 th (14) and 8 th (16) WAP compared to intercropping. These results are in agreement with [12] who stated that the number of leaves per plant is higher in sole cropping of okra than intercropping with cowpea. Wider spacing helps the okra to utilize its energy properly in the production of leaves because there was less competition for light, nutrients nor was overlapping from adjacent okra plants within the row may be the reason for higher number of leaf in monocropping. Similar findings were reported by [13] that, number of leaves per plant of okra is high in sole cropping than intercropping treatments with cowpea. But in contrast, [11] cited that, the number of leaves per plant of okra increased with intercropping with maize than sole cropping of okra.

Number of branches per plant
There were significant differences (P<0.05) in number of branches per plant with different planting patterns at 4 th , 6 th and 8 th WAP is confirmed with P values of 0.022, 0.009 and 0.000 with Chi square values of 13.13, 15.38 and 23.31 respectively is shown in Table 3. The higher number of branches was observed in T1 may be due to the free and wider spacing between planting rows compared with other tested treatments. So, okra plants used energy properly and produced higher number of branches per plant. Overlapping effect from adjacent plants was reduced in monocropping [14] and plants produced branches freely and properly without any restriction, by utilizing the plant's energy well. The number of branches were high in intercropping treatments than sole cropping of okra, when maize planted four weeks after planting of okra [15]. The finding is not agreeable with present study.

Leaf area
It was investigated that, leaf area was significantly different (P<0.05) among treatments at each weekly interval (Table 4). At each weekly interval, leaf area was highest in T5. Minimum leaf area was noted in T7 at 2 nd and 4 th WAP while it was in T6 at 8 th WAP. Light interception percentage is high in intercropping than sole cropping [16]. It explains that, reduced spacing between plants enhances the light interception. That may be the reason for the increase of leaf area in T5 compared 86 JHPR Volume 7 with T1. The leaf area was high in intercropped okra plants with maize than monocropping of okra [17]. In contrast, leaf area of okra was reduced when intercropping with sweet potato [18]. Higher leaf area values were obtained in sole cropping than intercropping of okra with cowpea [13].

Leaf Area Index (LAI)
There was a significant difference (P<0.05) in LAI at each two weeks interval (Table 5). Leaf area index (LAI) was found to be high in T5 at each weekly interval. At 2 nd and 4 th WAP, least value was found in T4 and T6 respectively while at 6 th and 8 th WAP, lowest leaf area index was found in T6. Leaf area index is an important parameter in plant growth as leaves are the most important aspect in photosynthesis. The increase in LAI in intercropping than sole cropping was due to the increase of plant population [19]. Higher plant population may produce a narrow canopy due to reduced space and intercept more light, without letting them to penetrate to the soil may be reason in the present study.

Chlorophyll content
Chlorophyll can be identified as one of the most important biochemical parameters of plants and indicate plants' nutritional stress, photosynthetic capacity and the health status of plants. Therefore, it is an important parameter used for ecosystem productivity estimation [20]. It was found that there was no any significant difference (P>0.05) in chlorophyll content among treatments at each weekly interval (Fig. 9). Chlorophyll content vary with different factors such as sunlight, climatic factors such as salt stress, soil type, elements like nitrogen and phosphorus, temperature, water content of leaves and some enzymatic reactions [21,22]. In the present study, the reason for not significant difference may be because of not having any affect from those factors. Chlorophyll content (SPAD value) of sole potato was higher than the potato and mustard intercropping treatment [9].

Canopy width
It was observed that canopy width was not significantly different (P>0.05) except at 6 th WAP ( Fig. 10). At 6 th WAP, canopy width was highest in T5 and lowest in T7. There was no significant difference (P>0.05) among the treatment except T5 at 6 th WAP. Canopy width increase in a linear manner with the increase of height [23] when height increase and due to the need of higher photosynthetic rate, light interception was high and this may cause the development of a higher canopy width in T5 at 6 th WAP.

Fresh weight of plant
There were no significant differences (P>0.05) at 2 nd , 4 th WAP is shown in Fig. 11. There was significant difference (P<0.05) in 6 th and 8 th WAP. At 6 th weeks after planting maximum plant weight was observed in T5 (109.64g) and minimum was observed in T7 (50.91g). While at 8 th WAP, maximum plant fresh weight of okra plant was observed in T5 (122.51g) and minimum was obtained in T7 (70.13g). At 6 th WAP, the variation may be due to production of higher yield due to higher light interception by taller plants of okra and due to lower soil and air heat because of reduced spacing. Higher plant density reduces soil and air heat [24]. Because lower soil and air heat reduced the water evaporation from soil and plant.  T1  T3  T4  T5  T6  T7 88 JHPR Volume 7 Figure 11: Fresh weight (g) of total plant of okra at two week interval

Fresh weight of leaves
There was significant different (P<0.01) at 6 th and 8 th WAP is shown in Table 6. Average leaf fresh weight is varies from 18.74g (T3 and T4) to 42.19g (T1) and 20.06g (T7) to 43.77g (T1) at 6 th and 8 th WAP respectively. This may be resulted from the higher number of leaves per plant in T1. Fresh weight of leaves of cauliflower was higher in sole cropping of cauliflower than intercropping with pea [25].  Fig. 12 showed that there was no significant difference (P>0.05) at 2 nd and 4 th WAP and significant difference (P<0.05) was observed at 6 th and 8 th WAP. The maximum stem weight at 6 th WAP was obtained in T5 (52.45g) and the minimum value was obtained in T7 (21.23g). At 8 th WAP, maximum value was found in T5 (63.46g) followed by T6 (42.33g). There were no significant differences (P>0.05) between T1, T5 and T6. Heat penetration to the soil may be also low to the treatment T5, due to the low spacing with higher plant density and it leads to low water evaporation from the soil. It may cause for the higher absorption of water from soil. In contradictory, stem fresh weight was high in intercropped okra with cowpea than sole cropping of okra [9].

Fresh weight of root
The results revealed that there were no significant differences (P>0.05) at 2 nd and 4 th WAP. But there was a significant difference (P<0.05) at 6 th and 8 th WAP is shown in Fig. 13. At 6 th week of planting, the highest fresh weight of root was obtained by T5 (12.72g) was par with T1 (8.45g). Minimum was obtained with T4 (5.16g) and it was not significantly differ from T3, T6 and T7. At 8 th WAP, highest value was found in T5 (16.96g) and minimum value in T7 (6.97g). Higher moisture content in soil may cause higher absorption of water to the roots. This higher moisture content may be due to the lower evaporation of water from soil due to the shading of soil due to the high population of cowpea and okra plants and also due to frequent irrigation. Soil and air heat may be low due to higher plant density with lower spacing [24]. And also, okra may accumulate more matter with the provision of N2 by cowpea. Root fresh weight of okra was high in intercropping with cowpea than sole cropping of okra [9]. Root fresh weight of okra was high in intercropping with cowpea than sole cropping of okra [12]. It is agreeable with this study.

Total dry weight
It was observed that there was no significant difference (P>0.05) at 2 nd and 4 th WAP. There was a significant difference (P<0.05) at 6 th and 8 th WAP (Table 7). At 6 th WAP, the highest mean value of total plant dry weight of okra was found in T5 (29.82g) and the lowest value was found in T3 (11.39g). This may be due to the availability of light to okra plant with their increased height which increase the production of photosynthates and their reflection on the plant growth, besides the direct transfer of fixed N2 from cowpea to okra plant. Dry weight of plant is higher in intercropping than sole cropping [8]. At the 8 th WAP, the highest mean value for total dry weight was observed in T5 (37.20g) and T1 showed no any significant difference (P>0.05) with T5. Up to 4 th WAP, both crops in intercrops and monocrops were in their vegetative stage. So, both use nutrients available in soil, without any effect of the spacing and excessive N2 supplement from cowpea, to grow in to maximum vegetative growth. And there was no much variation in between the heights of both okra and cowpea in each treatment at 2 nd and 4 th WAP. So, much competition for light also was not expected. Therefore, there was no any variation among treatments with light interception and dry matter accumulation up to 4 th WAP. So, that may have caused for no any significant difference (P>0.05) in total dry weight at 2 nd WAP and 4 th WAP. With supporting to the findings, it was found that total dry weight of okra is higher in intercropping systems with cowpea than sole cropping of okra [26].

Leaf dry weight
No significant differences (P>0.05) were observed in 2 nd and 4 th WAP and significant differences (P<0.05) were observed in 6 th and 8 th WAP (Table 8). At 6 th WAP, the highest value was observed in T5 (10.21g) followed by T1 (8.25) and the minimum value was observed in T3 (4.31g). At 8 th WAP, the maximum value was observed in T1 (13.75g) and minimum was observed in T7 (5.96g). These results coincide with the highest number of leaves per plant was in T1 may be the reason for higher dry weight of leaf in T1. Okra intercropped with cucumber as well okra intercropped with melon, gave higher leaf dry weight when compared to the sole cropping of okra [27] is disagreeable with this study.

Stem dry weight
It was obvious that there were no significant differences (P>0.05) in 2 nd and 4 th WAP. But the difference (P<0.05) was observed in 6 th and 8 th WAP (Table 9). Highest mean value was observed in T5 (14.36g) at 6 th WAP. Least value was observed with T7 (4.59g). At 8 th WAP, maximum dry weight was found in T5 (15.06g) and least was in T7 (6.03g). Higher stem dry weight may be due to the longer stem length. Higher planting density leads to grow taller. It grew taller to obtain sufficient sunlight and allocate more resources than sole planting with higher planting density [28]. Okra intercropped with cucumber, as well okra intercropped with melon, gave higher stem dry weight when compared to the sole cropping of okra [27]. Stem dry weight of okra was reduced with the increase of plant density in intercropping okra and celosia than monocropping of okra [29].

Root dry weight
It was investigated that, there were no significant differences (P>0.05) in 2 nd and 4 th WAP. The significant difference (P<0.05) was observed in 6 th and 8 th WAP (Table 10). The maximum value for root dry weight was obtained by T5 (5.48g) followed by T1 (2.89g). But, T3, T4, T6 and T7 didn't show any significant difference in root dry weight while minimum mean value was obtained by T3 (1.24g). At 8 th WAP, the maximum value was gained by T5 (5.98g) and minimum by T3 (1.71g). T5 and T1 as well T3, T4, T6 and T7 were not significantly different from each other. This may be due to higher light interception by the okra plants due to lower spacing than sole cropping and higher transformation of photosynthates. Okra intercropped with cucumber as well okra intercropped with melon, gave higher root dry weight when compared to the sole cropping of okra [27].

Cumulative yield
It was observed that there was significant difference (P<0.05) among tested treatment in cumulative yield (Table 11). The highest mean value was obtained in T5 (4.51t/ha) and the least value was observed in T3 (1.30t/ha). T1 T4 and T6 were not significantly different (Table 11). Higher light interception by taller plants and accumulate more photosynthates [24]. The results may be due to that reason.

Sun dried seed weight (for seed purpose)
It was revealed that there was no significant difference (P>0.05) in between treatments (Table  12). 100 seed weight was high in sole okra than intercrop with maize, irrespective of cropping system, with the increase of poultry manure rate [30]. They also stated that this may be due to easy solubalization effect of released plant nutrients that improved the nutrient status and water holding capacity and plant nutrients. So, that meant that there is no significant difference (P>0.05) in 100 seed weight with cropping system.

Area Harvest Equivalent Ratio (AHER)
The concept of AHER combines the area and time factors in a practical manner in order to quantifying intercrop yield advantages, particularly in multi-season associations. AHER was higher in T5 and the least was in T3 (Table 13). AHER was higher in turmeric and maize intercropping than sole cropping of turmeric and maize [31]. AHER showed a comparative advantage of multiple cropping over sole cropping when rubber is intercropped with melon and soybean. Rubber and melon showed a higher AHER of 2.41 while rubber and soybean showed a least value of 1.20 [32].

Conclusion
The present study was conducted to investigate the growth and dry matter accumulation of okra as influenced by different planting patterns under okra (Abelmoschus esculentus L.) cowpea (Vigna unguiculata L. Walp) intercropping in sandy regosol. It revealed that there were significant differences (P<0.05) in plant height, root length, fresh weight of total plant, dry weight of total plant, leaf area, leaf area index, canopy width, cumulative yield of okra and those were higher in the planting pattern of 60/150, with three rows of cowpea in between two pair of okra rows (T5). Chlorophyll content was not significantly different (P>0.05) with different planting patterns. Okra in T5 gave 17.1% higher yield than T1. In okra, there was no significant difference (P>0.05) in chlorophyll content, number of flowers per plant, seeds per fruit and 100 seed weight.
When the land is a scarce resource and if the nitrogenous fertilizer availability is limited or if those are with excess price, intercropping of okra and cowpea can be used as an eco-friendly alternative in producing higher quality okra fruits. And also the productivity of okra per unit land area can be increased with the intercropping systems. According to this study, when growth and yield are considered, it can be suggested that, among the all tested treatments, 60/150 cm treatment with paired row planting of okra with three rows of cowpea in between paired rows (T5) would be the most suitable planting system for sandy regosol.