Effect of spacing and phosphate fertiliser on forage and seed yield of Dolicho8 lab lab var. lignosus

Transcription

1 Annale oj A,.id Zone-14 (3), Effect of spacing and phosphate fertiliser on forage and seed yield of Dolicho8 lab lab var. lignosus C. M. VERMA Central Arid Zone Research Institute, Jodhpur ( Received on ) ABSTRACT Investigations on forage and seed production of Dolichoe lablab var. ligno8ub as influenced by spacings and levels of phosphorus were carried out at the Central Arid Zone Research Institute, Jodhpur. Inter-row spacing of 25 cm resulted in maximum forage yield but the effect of spacing treatments on the seed yield was not well marked. 'Significantly higher fodder yields were obtain~d with 40 and 80 kg P ha <over the control. Increase of the order of 2.0, 23.3 and 39.8 per cent in seed yield over control was recorded with the application of 20., 40 and 80 kg P205/ha respectively. Finally, the economic analysis of differential cost and return structure incidental to phosphatic fertilizer use indicated the usefulness of 40 kg p,05/ha INTRODUCTION Selection of plant material which would serve the dual purpose of providing nutritious feed to the livestock population and increase tbe soil fertility in the long run, should get preference in tbe rebabilitation of pasture lands. Dolichos /ab/ab (Sem)-a legume, commonly known as 'balar' fulfils these purposes. Despite its being an important fodder legume, the standardisation of its agro-technology for arid and semi-arid regions has not received the desired attention. This study was, therefore, conducted to find out the effect of spacing and optimal dose of phosphatic fertilizer on the perfor~ance and maximum herbage and seed production in the arid and semi arid regions of western Rajasthan. MATERIAL AND METHODS The investigations were carried out ( and ) at tbe Central R esea rch Farm of the Central Arid Zone Research Institute. Three

2 236 : C. M. VERMA spacings i.e. 25, 50 and 75 cm between rows formed the main plot treatments of split plot design. Four levels of tertilizer i.e 0, 20, 40 and 80 kg P205 per hectare were randomised in the sub plots within each plot (4m2, halo There were four replications. A basal dressing of 25 kg nitrogen (ammonium sulphate) per hectare was uniformly applied at the time of land preparation. Two seeds were dibbled in a hill at 30 em apart between rows. Only one seedling was kept.per hill after germination. Whole of the quantity of phosphatic fertiliser according to the treatment concerned were appiled at the time of sowing by placement. While the first set of experimental material was sown on aad the seeond set was sown on I and harvested on The date of collection of seeds was Morphological observations, i.e. height and number of branches were recorded on six plants selected at random before harvesting. For recording the height of plants, the criterion of mt:asuring the longest shoot was employed. The crop was harvested at the time of initiation of flowering and dry forage yield per hectare was recorded. FC'lrrecording the dry forage yields, 100 gm sample of green fodder from each sub plot was randomly picked up and oven dried. The seed yield was recorded after fuii maturity. But in the second year the data on seed yield were not recorded as, due to low precipitation and prolonged drought, the seed setting was drastically affected. Finally, in order to ascertain economic dose of phosphatic fertilizer differential cost-ben~fit structure of each dose was, computed. This was accomplished by evaluating forage seeds and fertilizer at the rate ot Rs , and per quintal respectively. RESULTS AND DISCUSSION Effect oj spacing on growth: Average height and number of branches per plant of Dolic.hos l'jblah observed during 1970 and 1971 are presented in Table I. Plant height: The differences in the height of the plants were found to be highly significant during the first year, whereas they were not significant in the second year. In both the years 50 em spacing exhibited maximulr height and minimum under 25 cm spacing. No significant differences were observed between 50 and 75 cm. sp cing treatments. Number nf branchu: Closer spacing of 25 cm between rows adversely affected the branches (Table I). Maximum numbers of branches per plant were produced by the rows spaced at 75 cm in both the years. However,

3 YIELD OF DOLlOHOS LABLAB ; 237 during 1971 when the rainfall was sub-normal the differences in the number of branching under different spacibgs were not significant. Table I. Effect oj spacing and phosphate fertiliser treatment on plant growth Treatments Height in em No. of branches Row spf1cings 25 em 50 em 75 em SEm ± C. D. at 5% C. D. at 1% I0.8 II ' g8 \ PhoJphute lelle/s Control 20 kg/ha 40 kg/ha 80 kglha SEm ± C. D. at 5% C. D. at 1% ;97 Increase in plant height and number of branches under 50 em and 75 em spacing was ob~iously due to less competition for nutrients. Effect of jertilisers on the growth: The data on the height and number of branehes per plant due to the effect of varying doses of fertiliser have been presented in Table I. Plant height: The plant height was markedly affected by the application of fertiliser. Maximum height (164.3 and em in the first and second year respectively) was attained by the plants receiving fertiliser at the rate of 80 kg P Z 05 per hectare and the differences were significant when compared.with the other levels of feniliser in both years.

4 238 C.M. VERMA Number oj branches : The overall number of branches produced ranged between 17 and 21 and between 13 and 17 in he first and second year respectively. The plants receiving 80 kg P205 per hectare exhibited increased production of branches over other treatments. Growth in poorer in the second to lower precipitatio height and production of branches were comparatively year.as compared with first year. This was perhaps due in the second year. Eifut of spacing on forage and seed production: The data on forage and seed yield as affected by row spacing are presented in Table 2. Table 2. Effect of row spacing on dry forage and seed yield in quintal per hectare Treatments Dry forage yield Seed yield Row spacings 25 em em cm SEm± C.D. at 5% 1.85 N.S. N.S. C.D. at 1% 2.80 The effect of different row spacings on forage yield was highly significant in the firsr year but it was not significant during the second year. However, the maximum forage yield has been recorded from 25 cm spacing: followed in order by those from 50 and 75 cm spacings. These differences were mainly because of higher plant population per unit area in 25 cm spacing treatment. These results are in coformity with those of Faroda (1975). The differences in tte seed yield were not sigificant. The results obtained for the two consecutive years show that application of phosphate had encouraging effect on the forage production. All three phosphate levels increased the forage yield over the control in both the years. However, significantly increased forage yield was observed at the rate of 20 kg P205 per hectare during the year 1971.

5 YIEI,D OF ljollohos LABLAB 239 Effect of fertiliser on forage and seed production : Table 3. Effect of phosphate fertilizer treatments on forage and seed yie Id in quintals per hectare Treatments Dry forage yield Seed yield 197~0--- Phosphate levels Control kg/ha kg/ha kg/ha SEm± C.D. at 5~~ C.D. at 1% N.S. Highest forage yield was recorded by the applicatiun of 80 kg P205 per hectare in both the years. the percentage increase over control being 41.3 and 56.0 in the first and second year respectively. Similarly, 40 kg P 2 05 per hectare also resulted in 29.5 and 32.5 per cent increase over comrol during first and second year respectively. Dolichos lab lab responded well to phosphate applications as it produced higher seed yield at all levels of phosphate application in comparison with the control (Table 3). The percentage increase over control was and 39.8 by and 80 kg P206 per hectare respectively. The superiority of the 80 kg/ ha phosphate treatment over the other treatments appears to be mainly due to the: better utilisation of nutrient resulting in better crop growth, as indicated by plant height and increased number of branche sper plant. The interactions between the spacings and application of fertiliser were npt found to be significant in botb the years. However, the differences between the seed production remained unaffected by the treatments of different levels of fertilizers. Comparative economics of PhosPhatic fertilizer use,. Despite the limitalions inherent in the study, comparative benefit: cost ratios incidental to the added doses of fertilizer requirements were worked out (Table 4).

6 240 C. M. VERMA Table 4. Economics of phosphatic fertilizer use Treatments Gross returns (seed and forage) Input Rs. Basal differential gains 61 Po (%) Interdose differential gains 62 P (%) PhosPhate Itve[s Control 1685.' kg/ha kg/ha kg/ha It is evident that every added dosage of phosphatic fertiliser to legume have contributed more to the gross revenues by percent, for 20 kg P205' per cent for 40 kg R205 and per cent for 80 kg P205' It is obvious from this comparison that addition of further dose$ of fertilizer Q,ver level of 40 kg P205 per ha might herald the diminishing marginal tendency of the responsiveness of fertilizers. When the contribution was compared within each additional dose, it was further confirmed that fertilization beyond 40 kg P205/ha might cause less than proportionate net yields. ACKNOWLEDGEMENTS The author is grateful to Dr. H.S. Mann, Director, Central Arid Zone Research Institute, Jodhpur for providing necessary facilities for the work and for going through the manuscript. Thanks are also due to Shri A.K. Chakravarty, Ex- Head, Division of Resource Utilisation, for his help and encouragement and to Mr. j.c. Kalla, Production Economist, for suggesting the ap.p.roach for economic analysis. REFERENCE Faroda, A.S. (1972). Effect of seeding rates and row spacings on fodder production of Moth Bean (Phaseolus aconitilolius). Ann. Arid Zone, 11 :