EVALUATION OF EARLY MATURING SORGHUM [SORGHUM BICOLOR (L.)MOENCH] AND COWPEA [VIGNAUNGUICULATA (L.)WALP.] VARIETIES INTERCROPPING FORBIOMASS YIELD IN FEDIS DISTRICT, EASTERN ETHIOPIA

1. Oromia Agricultural Research Institute, Fedis Agricultural Research Center, East Hararghe Zone, Harar, Ethiopia. 2. College of Agriculture and Environmental Sciences, Haramaya University, Haramaya, Ethiopia. ...................................................................................................................... Manuscript Info Abstract ......................... ........................................................................ Manuscript History Received: 22 March 2020 Final Accepted: 25 April 2020 Published: May 2020

The shortage of arable land and shortage of livestock feed are major constraints in East Hararghe Zone. Thus, a field study was conducted to evaluate early maturing sorghum and cowpea varieties intercropping for feed production at Fedis Agricultural Research Center, eastern Ethiopia in 2018 cropping season. With a total of 11 treatments; Two cowpea varieties (9333 and 9334) and three varieties of early maturing sorghum (Teshale, Birhan and Melkam) and their intercropping compared with sole cropping of all the varieties, which were laid out in a randomized complete block design with three replications. The result showedaboveground dry biomass of sorghum was highly significantly (p < 0.01) affected due to sorghum varieties. The highest aboveground dry biomass of sorghum (6.99 t ha -1 ) was obtained from sorghum Melkam + cowpea (9334) intercropping. The aboveground dry biomass yield of cowpea was significantly (p < 0.01) different due tointercropping. The maximum aboveground dry biomass yield of cowpea (8.19 t ha-1) was recorded for sole cowpea (9333). Generally, the results of this study showed that intercropping of sorghum-cowpea were increased the production of biomass yield of sorghum varieties. Based on the results of this study, it concluded that intercropping sorghum with forage cowpea; preferably, sorghum Melkam + cowpea (9333) to appropriate to increase Biomass yield in the study area.
Intercropping provides an opportunity to harness available resources by the cultivation of two or more crops planted simultaneously in the same land that provides the possibility of yield benefit and minimize crop failure (Bhattiet al.,

ISSN: 2320-5407
Int. J. Adv. Res. 8(05), 1187-1196 1188 2006). A major benefit of intercropping is an increase in production per unit area compared to sole cropping through the effective use of resources (water, nutrients, and solar energy), which reduces weed competitions and stabilizes the yield (Nasriet al. 2014). Farmer generally takes decisions on the technologies to adopt on the bases of cost, risk and return calculation. In small-scale farms, the farmers raise as risk-minimizing measures against total crop failures and the Intercroppingsystemhas long been practiced by smallholder farmers in various tropical and sub-tropical regions worldwide (Brookeret al., 2016).
Sorghum is potential crops in the study area and the average yield production of sorghum is 2.05 t ha -1 in Ethiopia and 2.19 t ha -1 in the region. The low productivity of sorghum in developing countries including Ethiopia could be attributed to many biotic and abiotic factors, like erratic rain full, disease and pest and low soil fertility (CSA, 2017). It considered one means of alleviating the challenges of recurrent drought in Ethiopia. The released varieties have a yield potential of 4.0 to 6.0 t ha -1 , which are two to three-fold higher from the national average yield (Taye, 2017). However, there has been limited adoption rate of the improved varieties mainly due to lower biomass production of these varieties in comparison to the landraces (late matured). In order to address the demand for food, feed and fuel farmers predominantly prefer to grow the late maturing sorghum landraces in the majority of dry lowland sorghum growing areas of the country, which requires more than seven months to reach maturity and on the other hand, the released early maturing sorghum varieties have the capacity to escape and/or resist terminal drought stress (Taye, 2017).
Cowpea is among the most widely used legumes in the tropical world. It can be incorporated into the cereal cropping system to address soil fertility decline and cereals to the provision of better legume/stover to cereal (Cooket al., 2005). Food production systems, particularly in cropping systems with limited external inputs, this may be due to some of the potential benefits for intercropping systems such high productivity and profitability (Yildirim and Guyenc, 2005), and farmers can cut and store cowpea fodder for sale at the peak of the dry season Cowpea can be grown under rainfed conditions as well as by using irrigation or residual moisture along river or lake flood plains during the dry season, provided that the range of minimum and maximum temperatures is between 28 and 30 °C (night and day) during the growing season. Cowpea performs well in agro-ecological zones where the rainfall range is between 500 and 1200 mm/year (Madambaet al., 2006).
In East Hararghe Zone, livestock is greatly dependent on crop residues for feed and the farmers usually harvest fodder from thinned crop plants, weeds, and defoliated leaves (Kassa, 2003). However, plants could suffer from severe competition during the early growth stages due to overpopulation and fodder production could be at the expense of grain yield, is thus desirable to generate alternative technologies that enable to produce forage for livestock and enhance efficient utilization of sorghum residue without significant change in sorghum grain yields. In general, intercropping is more productive than mono-cropping (Iqbalet al., 2018). Ina study as a whole, intercropping is the main and indigenous activity of the farmers due to land shortage. Most of the farmers are practicing intercropping of different crops for different reasons like to minimize total crop failure and efficient land utilization is the main target. Mixtures of sorghum-legume showed advantages in land-use efficiency expressed as LER than monoculture sorghum (Iqbalet al., 2018).Areas where intercropping is practiced, crop yield is enhanced simply by growing two or more compatible crops without using costly agricultural inputs. Therefore, the objective of this study was to evaluate an early maturing sorghum and cowpea varieties intercropping for both food and feed production with the following specific objectives: To evaluate stover yield of sorghum and herbage yield of cowpea under intercropping conditions The livelihoods in the district comprise of agro-pastoralists and pastoralists the rainfall is bimodal with the Kiremt rain being important in the crop-dependent areas. Fedis is one of the lowland districts with a total population estimated to be 133,382 persons, of which the estimated urban population was 26,575 and the estimated rural population was about 127,877. The main sources of income are agriculture (particularly chat and livestock sales), self-employment (firewood sales) and local labor (harvesting and packing chat). Sorghum and maize are grown for home consumption (ACLFE, 2014).

Description of Experimental Materials:
Two-cowpea varieties (9334 and 9333) were used with three varieties of early maturing sorghum (Teshale, BirhanandMelkam). The experimental materials were selectedbased on their current and potential importance and mainly on their productivity and heights of the plants. Thus, all experimental materials were obtained from Fedis Agricultural Research Center and well performed under the agro-climatic condition of the area. The experiment was done under rain fed conditions.

Treatments and Experimental Design:
Sole cowpea and sorghum, under sorghum-cowpea intercropping, was laid out in a randomized complete block design (RCBD) with three replications in a plot area of (33) m 2 , 1m between plot and 1.5m between block. Sorghum was planted on June 28, 2018 at a spacing of 75 cm between rows and 20 cm between plants for sole and intercropping, while cowpea which planted twenty days later (on July 18, 2018 ) after sorghum was sown. Sole and intercropped cowpea were planted at a spacing of 37.5cm between rows and 10 cm between plants. Sorghum-Cowpea intercropping were planted 1:1 row arrangement as a recommended of Tajudeen and Aliyu (2010)with seed proportion of intercropping 100:100 sorghum + cowpea respectively

Experimental Procedure and Field Management:
Land preparation was done in the middle of April with a tractor, harrowed and leveled before planting. The seed rate of 12 kg ha -1 kg ha -1 for sole and intercropping sorghum was planted at a row spacing of 75 cm through drip sowing with 5cm deeps when the soil has enough moisture for seed germination then later after 20 days of planted sorghum were sown cowpea varieties the seed rate of 30 kg ha -1 for sole and intercropping with a spacing of 37.5 cm for all sole and intercropping.NPS (19% N, 38% P 2 O 5 and 7% S) and Urea (46% N) each at the rate of 100 kg ha -1 and NPS during planting and Urea after plants emerged 2-3 leaves were used. After emerged of two-three leaves it was 1190 thinned and manuals did weeding or through hands with frequently when the weed is emerged and hoeing two times at early stage and after heading the panicles. The forage samples preparation for quality parameters was done in well precaution manners.

Data Collection and Measurement: Sorghum component: Phenology and growth parameters:
Days to 50% flowering: it was recorded as the number of days from planting to 50% of plants per net plot produced a flower Days to 90% physiological maturity: it was recorded as the number of days from planting up to 90% of plants in each net plot formed a black layer on the base of the kernels, which was an indication of maturity.

Leaf area (LA):
Five plants per net plot were randomly taken to measure leaf area per plant (cm 2 ) at 50% heading using the method described by Sticker et al. (1961) as leaf area = length of the leaves × maximum width of leaf × 0.75 where 0.75 is the correction factor for sorghum.

Leaf area index (LAI):
the leaf area index was calculated as the ratio of unit leaf area per plant to the ground area covered by the plant Plant height: it was measured at physiological maturitywhich when the plants became harvesting from the ground level to the tip of panicle from five randomly taken plants and was averaged on per plant basis by using 5m scaled meter.

Aboveground (stover and dry) biomass (g):
it was taken by used 10 plants from the net plot area of plants after grain yield was harvested as soon for herbage and chopping into 5 cm-8 cm length and then sun-dried till constant weight for dry biomass and then converted tone per hectare basedby (10 x TotFW x (DWss/ HA x FWss)) (Tarawaliet al., 1995). Where; TotFW = total fresh weight from a plot in kg, DWss = dry weight of the sample in grams, FWss= fresh weight of the sample in grams, HA = Harvest area meter square and, 10 = is a constant for conversion of yields in kg per m 2 to t ha -1 Cowpea component: Phenological and growth parameters: Days to 50% flowering: It was recorded as the number of days from the date of emergence to when 50% of plants in a plot produced a flower.

Days to 90% physiological maturity:
It was recorded as the number of days from the date of emergence when 90% of plant leaves and pods changed to yellow

Plant height (cm):
Was measured from the middle rows on five randomly taken plants at the flowering stage from the ground to the tip of the plant using 5 m tape.

Aboveground dry biomass weight (g):
It was measured from one row randomly selected from net rows of the plot at 50% flowering stage as soon cutting, then converted to per hectare based; by using the sensitive balance. The dry matter production (t ha -1 ) was calculated as: -(10 x TotFWx (DWss/ HA x FWss)) (Tarawaliet al., 1995).Where: TotFW = total fresh weight from a plot in kg, DWss = dry weight of the sample in grams, FWss = fresh weight of the sample in grams, HA = Harvest area meter square and, 10 = is a constant for conversion of yields in kg m 2 to t ha -1 1191 Statistical Analysis: Data were analyzed using the Statistical Analysis Software to perform ANOVA (SAS 9.1, 2004) in a randomized complete block design. Means of all treatments were calculated and the difference was tested for significance using the least significant difference (LSD) test at p < 0.05 (Gomez and Gomez, 1984).
Statistical model was: Yij= μ + τi + βj + εijk , where µ = the overall mean, τi = the treatment effect i th , βj =the block (replication) effect ofj th replication and ∈ijk = error effect Results and Discussion:-Sorghum Component: Crop phenology, Growth parameters and Biomass yield: Days to 50% flowering: of sorghum was recorded and obtained as in Table (1) shows that a significantly different (p < 0.05) level of significance among the varieties of sorghum Birhan and Teshale, Birhan and Melkam but statistically not significant among Teshale and Melkam, also not significantly different among cropping systems(intercropping). The maximum days to 50% flowering (79.67days), that obtained from sorghum melkam. Whereas early flowering was obtained from sorghum Birhan (72 days). The intercropping was not affected days to 50% flowering may due to the gap of planting date of sorghum and cowpea (20 days) so that the planting cowpea was not covered in a good manner under the sorghum for further moisture conservation, nitrogen fixation of the soil and not protect the entrance of solar radiation during the flowered of sorghum.
Days to 90% physiological maturity (Dm): was highly significant different (p < 0.01) amongsole and intercropping and varieties of sorghum. In Table (
The incremental of plant height of sorghum under intercropping of cowpea might be due to soil moisture conservation.Thus, Result disagrees with the result that reported of Islamet al. (2018) in Pakistan intercropping reduced plant height, sole millet gave maximum height (250.33 cm) and the minimum produced plants of (241 cm) one row of millet alternating with one row of cowpea. The difference may be due to the behaviors (varieties) of the plants and seed proportion. Means within the same column followed by the same letter or by no letters of each factor do not differ * = significant different (0.05), ** = significant different (0.01) significantly at 5% probability level, Df = days to 50% flowering; Dm = days to 90% maturity; LAI = leaf area index, plh= plant height in centimeter, LSD = Least signifAGHY = above ground herbage yield, ADBM = above-ground dry biomass icant difference; CV= coefficient of varianceT1 = Cowpea (9334)  Aboveground stover and dry biomass yields (t ha -1 ): the result that obtained dry biomass and stover yields of sorghum in Table (1) was highly significant among sorghum varieties. However, it was non-significant betweensole and intercropping of sorghum stover. However, intercropping was numerically increased above ground stover yield and dry biomass yield except Sorghum Birhan intercropping. The highest aboveground stove herbage biomass yield was obtained from T6(14.47 t ha -1 ), T3 (14.22t ha -1 ) and T10 (14.05t ha -1 ) and the highest aboveground dry biomass yield was obtained from sorghum T3 (6.99 t ha -1 ), T6 (6.61t ha -1 ) and T1 (6.37t ha -1  with sorghum varieties as shown in a Table (2) the maximum Df 50% was recorded of T1, T3 and T7 (68 days), followed by T2 and T6 (67 days and 65 days) respectively. The minimum days to 50% flowering of was recorded of cowpea varieties (9333) sole and there intercropped of (T4, T5 and T8 (61.33, 61.67 and 61.67) days) respectively. Because of early maturing sorghum (main crops) had a shorter height, smaller leaf area and leaf area index so not much protection as a shade from solar radiation especially at this stage except T6; intercropping was increased days of flowering by 5.35% because sorghum Melkam had leaf area was highest than the main tasted crops.

Days to physiological maturity:
The result showed highly significant differences among cowpea varieties and within their intercropped. The result in Table (2) of sole cowpea (9334) (T7) and cowpea (9334) + sorghum Melkam (T3) had a significant. However except T3 among sole and intercropping, there was no statistically significant, but numerically intercropping increased days to maturity. The late days to maturity recorded of T3 (109.33 days) T2 (108 days) and T1(106.33) where the early days of maturity were obtained from sole cowpea(T8), cowpea (9333) + sorghum Birhan (94 days) and T4 (94.67days). Days to maturity of cowpea affected by plant height of the sorghum Means within the same column followed by the same letter or by no letters of each factor do not differ significantly at 5% probability level, * = significant different (0.05), ** = significant different (0.01) LSD= Least significant difference; CV= coefficient of variance; Df=days to flowering; Dm=days NP/P = number of pods per plant; NS/P = number of seeds per pod, HSW = hundred seed weight in;maturity and pth=plant heights, Ns= none significant(0.05), ), AHY = above ground herbage yield; ADBY = aboveground dry biomass yield; GY = grain yield; agreed with the finding of Thomas and Eliakira (2014) cowpea intercropping with maize, pods per plant differed significantly obtained in cowpea planted in the sole and those obtained from the intercropping system.

Seeds per pod and 100 seed weight:
the data pertaining to the number of seeds per pod not influenced by varieties and cropping system indicated no significant differences (p > 0.05) among all treatments. The lowest 100 seed weights were obtained from cowpea (9334) under sole and intercropping ranges (8.10 g to 7.70 g). Thus result indicated that plant height of the main crop affected hundred seed weights of cowpea (9333) statistically and thus result in variations was may be due to the size of a seed, relative dominancy among the main crops and competition ofenvironmental growth resource and the shading effect of sorghum.

Above ground herbage (fresh) yield of cowpea:
The result indicated that in (Table 2) a highly significant difference (p <0.01) among cropping systems (sole and intercropping cowpea) but aboveground herbage yield not significantly affected by cowpea varieties. The maximum above ground herbage yield of cowpea recorded from T7 (sole cowpea (9334)) and T8 (sole cowpea (9333)); (46.7 t ha -1 and 45.47 t ha -1 ) in a consecutive manner. The minimum herbage yield obtained of T1 and T3;(16.29 t ha -1 and 15.8 t ha -1 ) respectively. Thus major significant variation mainly due to the distances betweenrows of cowpea among sole cowpea and under cowpea-sorghum intercropped and the entrance of solar radiation for photosynthesis due to shading effect. Similarity with the finding of Surveet al. (2011) when the row proportion of the legume intercrop was increased, enhanced but overall biomass production was decreased.
For smallholder farmers' perspective and selection availability; in addition to statistically, numerically which cowpea better compatible with sorghum varieties in a constant manner must issue. Based on this idea cowpea (9334) herbage yield affected by plant heights and leaf broadness of sorghum than cowpea (9333). In Table ( This increment order of dry biomass yield might be due to the shading and solar radiation entry attributed by sorghum. The increment in dry biomass production of sole cropped cowpea might be attributed to seed proportion of cowpea varieties, absence of competition and thus, more dry matter accumulation in stem, branches and leaves matter because of its good vegetative cover to harvest ample solar radiation important for its photosynthesis. This result confirmed with the findings of Karanjaet al. (2014) who reported that sole cropped gave higher dry biomass yield than the intercropped. Likewise, Getachewet al. (2013) reported that dry biomass of forage legumes was significantly affected due to sole and intercropping when intercropped with maize. Iqbalet al. (2012) conducted a field experiment on the productivity of summer legume forage intercropped with maizethe highest dry matter yield (2.039 t ha -1 ) was obtained from cowpea.

Summary and Conclusion:-
Ethiopian has a large livestock population and diverse agro-ecological zones suitable for livestock production and growing diverse types of food and fodder crops. However, livestock production has mostly been subsistenceoriented and characterized by very low reproductive and production performance; due to primarily shortages of quality and quantity of animal feed. Mainly due to land degradation, land shortage and poor soil fertility and rapidly increasing human population pressure and as a result, cropping was expanding and grazing areas are shrinking through time to time with including East Hararghe Zone. Therefore,the study was conducted to evaluate an early maturing sorghum and cowpea varieties intercropping for their herbage, grain and stover yields in FedisDistrictEast Hararghe, Ethiopia in 2018 cropping season under rainfed conditions. Therefore,it concluded that use intercropping of sorghum with forage legumes preferably sorghum Melkam + cowpea (9333) recommended for farmers for the production of forage in the study area and other areas with similar agro-ecological conditions.