African Crop Science Journal African Crop Science Society ISSN: 1021-9730 EISSN: 2072-6589 Vol. 7, Num. 4, 1999, pp. 407-413

African Crop Science Journal, Vol. 7. No. 4,  pp. 407-413, 1999

MAIZE RESPONSE TO METHOD AND RATE OF MANURE APPLICATION

T.H. Mubonderi , I.K. Mariga, L.M. Mugwira and O.A. Chivinge
Department of Crop Science, University of Zimbabwe, P.O. Box MP 167, Harare, Zimbabwe

Code Number: CS99031

ABSTRACT

Field experiments to determine the effect of solid beef manure application method and rate on maize grain yield and maize dry matter yield were carried out in Chinyika Resettlement Area (CRA) in Zimbabwe in the 1996/97 and 1997/98 seasons.  Four rates of manure (5, 10, 20, 30 t ha^-1) were applied using two methods: broadcasting and banding laid out as a 4 x 2 factorial in a randomised complete block design with three replicates.  Other treatments used were the extension recommendation, farmer practice, control and no basal fertiliser application.  Maize plants were sampled at 5, 10 and 15 weeks after crop emergence (wace) for dry matter yield at one site.  There were no significant effects of manure application method and rate on maize dry matter yield at 5 wace in both seasons.  At 10 wace in the 1996/97 season banding resulted in significantly higher maize dry matter yield than broadcasting (P < 0.05).  There was also a significant (P < 0.01) increase in dry matter yield with manure application rate.  At 15 wace there were no significant effects of manure application method on maize dry matter yield in both seasons.  Maize grain yield increased significantly (P < 0.001) with an increase in manure application rate at both sites in both seasons, and band application of manure resulted in higher maize grain yield than broadcasting at all manure application rates in both seasons. Band application of 30 t ha^-1 manure resulted in the highest net benefit.  Economic analysis indicated that 10 t ha^-1 banded was the economical manure application rate in both seasons.  The current general recommendation by extension agents is effective for dry - land maize production.

Key Words: Band application, beef manure, Zea mays, Zimbabwe

RÉSUMÉ

Des essais en champs ont été conduits durant les saisons de 1996/97 et 1997/98 dans la zone de repeuplement au Zimbabwe pour déterminer des effets du taux et de la méthode d’application de la fumure solide du boeuf sur le rendement en grains et le rendement en matière sèche du mais.  Quatre taux de fumure (5, 10, 20, 30 t ha^-1) ont été appliqués utilisant deux méthodes: semis à la volée et répartition en bandes comme factoriel 4 x 2 dans un bloc complétement rendomizé avec trois répétitions.  Autres traitements comprenaient la recommendation de la vulgarisation, la pratique du fumier, le contrôle  et  la non application d’engrais de base.  Les plantes de maïs étaient échantiollonnées à 5, 10 et 15 semaines après emergence (SAe) pour le rendement en matière sèche à un seul site.  Il n’yavaient pas d’effets significatifs du taux et de la méthode d’application de la fumure sur le rendement en matière sèche du maïs à 5 SAE dans les deux saisons.  A 10 SAE dans la saison de 1996/97, la répartition en bandes a donné un rendement en matière sèche siginificativement plus élévé plus que le semis à la volée (P<0.05). Il yavait aussi une augmentation significative (P < 0.01)  du rendement en matière sèche avec le taux d’application de la fumure.  A 15 SAE, il n’y avaient pas d’effets significatifs de la méthode d’application de la fumure sur le rendement eu matière sèche du maïs dans les deux saisons.  L’application en bandes de la fumure a aboutit à un rendement en grain plus élevé plus que le semi à la volée pour tous les niveaux d’application de la fumure dans les deux saisons. L’application en bandes de 30 t ha^-1 de fumure s’est soldée par un bénifice net dans les deux saisons.  L’analyse économique a révélé que le taux d’application de 10 t ha^-1 de la fumure en bandes était le plus économique pendant les deux saisons.

Mots Clés: Fumure de boeuf, Zea mays, application en bandes

Introduction

Manure from livestock is an important source of nitrogen for crop production in the smallholder sector and can help farmers reduce inputs of commercial fertiliser and increase the enterprise profitability (Schleich, 1986). The cost of commercial fertiliser in Zimbabwe has more than doubled over the last five years while the buying price of maize at the Grain Marketing Board has only increased by 30% over the same period.  This rising cost of inorganic fertiliser has made manure management more important than ever for the smallholder farmer.

The most common method of manure application used by smallholder farmers is broadcasting before ploughing although a few band it in the planting furrow (Munguri, 1996).  The interaction of manure application method and rate must be known in order to design application practices that maximise profits for the smallholder farmer (Murwira and Kirchmann, 1993).  The objective of this study therefore was to determine the influence of the method and rate of manure application on maize dry matter and grain yield.

Materials and Methods

Manure analysis. Cattle manure  was obtained from local farmers at whose farms  the experiments were conducted. Total nitrogen in manure was determined by the Kjeldahl method.  Total carbon was determined after dry combustion on an induction furnace after freeze drying. Total potassium was determined by flame photometry after dry ashing, and solubilisation in 1M hydrochloric acid.  Total phosphorous was measured colorimetrically after reaction with ammonium molybdate vanadate. The results of the analysis are shown in Table 1.

Table 1. Chemical properties of manure

Soil sampling and analysis.  At each experimental site the soil was sampled to a depth of 30 cm at planting before manure application for analysis of soil pH, total N, available P and K and organic carbon. Soil pH was measured in a 1:1 soil:water  suspension. The total nitrogen in manure was determined by the Kjeldahl method.  Organic carbon was determined by the Walkley Black method. Extractable (total P) potassium was determined by flame photometry and the available phosphorous (total P) was measured colorimetrically after extraction with Mehlich 3 reagent. Soil characteristics are shown in Table 2.

Table 2. Soil chemical properties of the three study sites

¹Available P in parts per million
²Available K in parts per million

Sites and experimental design. The experiment was conducted on - farm at two sites in Chinyika Resettlement Area (Chinyudze and Bingaguru villages) and on a researcher-managed site at Domboshava during the 1996/97 and 1997/98 cropping seasons.  Each gross plot measured 6 m².  An early maturing three - way maize hybrid (SC 501) was planted at an in-row spacing of 0.3 m (37,000 plants ha^-1).  For both seasons maize were planted in the first week of December.  The plots were weeded at 2 and 5 weeks after crop emergence (wace).  Maize stalk borer (Buseola fusca) was controlled by the application of dipterex (2.5% tri-chloroform) at  5 wace.  Amount of rainfall was recorded daily at individual sites.  The basal fertiliser used in this experiment was compound D (8%N, 14%P₂O₅, 7%K₂O, 6.5%S) at  a  rate  of  300  kg  ha^-1.  Nitrogen was top dressed as ammonium nitrate  (34.5%N) at  a rate of 86  kg  ha^-1 at 5 wace.  Four rates  of  manure (5, 10, 20  and 30 t ha^-1) were applied using two methods: broadcasting and banding.  These treatments were laid out as 4 x 2 factorial in a randomised complete block design with three replicates. Other treatments used in the experiment were the extension recommendation, farmer practice, control and no basal fertiliser application to give a total of 12 treatments.

Maize dry matter. Two representative maize  plant samples were taken randomly at 5 weeks intervals from the second and fifth rows.  The plants were cut at the base just above the soil surface.  The samples were oven-dried at 60ºC for four days and weighed.

Data analysis. Maize dry matter and grain yield data were analysed for each site using standard analysis of variance (ANOVA) procedures.  Combined ANOVA across sites was done after Bartlett’s Test showed that the sites had homogenous variances indicating that this test was valid.  Treatment means were separated using LSD.  Grain yield data were  subjected to economic analysis using the procedure of CIMMYT (1988).

Results

The main effects were significant in both seasons resulting in increasing grain and dry matter yields with increasing rates of manure.  Yields were higher with band application than with broadcast applications. There was a significant (P<0.05) interaction between method and rate of manure application for maize dry mater yield at 10 WACE in the 1996/97 season and for maize grain yield in the 1997/98 season.

Maize dry matter yield. There were no significant effects between method of manure application and manure rate on maize dry matter at 5 wace in both seasons. At 10 WACE there were significant effects of manure rate and method of application in the 1996/97 season only.  Banding resulted in significantly higher maize dry matter (P<0.05) than broadcasting.  There was also a significant (P<0.01) increase in maize dry matter with manure application rate, but interaction between method and rate of manure application was significant (Fig. 1 ).

At 15 WACE there were no significant effects of manure application method on maize dry matter in both seaons.  However, the rate of manure application had a significant effect on maize dry matter in the 1997/98 season (Table 3).

TABLE 3. Effect of manure application rate on maize dry matter yield at 15 weeks after crop emergence

NS = Not significant

The control had the lowest maize dry matter yields but was not significantly different from the manure treatments at 5 WACE.  The extension recommendation resulted in the highest maize dry matter at all stages of crop growth in both seasons (Table 4).

Table 4.  Effect of manure and fertiliser on maize dry matter production

WACE = Weeks after crop emergence

Grain yield. The main effects were significant in both seasons with band application resulting in significantly (P<0.05) higher grain yield than broadcasting at all manure application rates (Table 5).  The grain yield increased significantly (P< 0.001) with increase in manure rate and there was no interaction between method and rate of manure application in the 1996/97 season (Fig. 2). In the 1997/98 season there was a significant (P<0.05) interaction between method and rate of manure application (Fig. 3). Application of 30 t ha^-1 manure banded increased grain yield by 52% over broadcasting  while   application  of 5, 10  and  20 t  ha^-1 manure banded resulted in smaller increases over broadcasting. The no basal and control treatments had the lowest grain yield in both seasons (Table 5).  Application of 30 t ha^-1 manure  banded gave the highest grain yield in both seasons.

Table 5. Manure and fertiliser effects on maize grain yield

Economic analysis. Banding was used in this analysis.  Application of 30 t ha^-1 manure resulted in the highest net benefit in both seasons (Table 6).  The farmer’s practice was dominated by the application of 10 t ha^-1 manure in the 1996/97 season only.

Table 6.  Dominance analysis

Discussion

The high manure application rate (30 t ha^-1) gave the highest grain yield.  This could be attributed to increased available nitrogen and/or an increase in the soil water holding capacity.  However, this rate of manure application is unlikely to be feasible in Chinyika where the mean herd size is 11 (Munguri, 1996). In both seasons the band application of 10 t ha^-1 manure was more profitable than the farmer practice and in the 1996/97 season (a good rainfall season) farmer practice was dominated by band application of 10 t ha^-1 manure.  This result tends to agree with Grant (1981) who recommended 10 t ha^-1 manure plus 60 kg ha^-1 N as top dressing. However, the extension recommendation was more profitable than band application of 10 t ha^-1 manure in both seasons.

Maize dry matter yields from the plots which received manure did not differ from those in the control plots at 5 wace.  The dry matter yields at 10 wace from manure treatments were, however, higher than those of the control.  This suggests that there was low nitrogen release from manure in the early growth stages of the maize as suggested by Kirchmann (1985). The results generally suggest that method of manure application is not important in terms of final dry matter accumulation in maize. The current extension recommendation and farmer practice gave higher dry matter yields than most of the manure/inorganic N combinations and the control.  This suggests that the use of compound D as basal fertiliser meets the maize nutrient requirements better than the manure treatments used in the experiment.

In general, the results from this experiment have clearly shown that banding of cattle manure is more effective than broadcasting.  This method of application is therefore recommended since it allows effective use of the manure at lower rates.  The results also indicate that the current extension recommendation is effective although some smallholder farmers cannot afford inorganic fertiliser.  The farmers’ practice of applying basal fertiliser 2 WACE (only to emerged plants) also performed well suggesting good and rational use of resources by the farmer.

Acknowledgment

Funding for this study was provided by the Rockefeller Foundation's Forum on Agricultural Resource Husbandry for which we are very grateful.

References

CIMMYT, 1988. From Agronomic Data to Farmer Recommendations: An Economic Training Manual. pp. 1-79.  Completely revised edition. CIMMYT, Mexico, D.F.

Grant, P. 1981.  The fertilization of sandy soils in peasant agriculture.  Zimbabwe Agricultural Journal 78:169-175.

Kirchmann, H. 1985.  Losses, plant uptake and utilization of manure during a production cycle.  Acta Agriculture Scandinavia Supplement 24:5 -77.

Munguri, M. W. 1996.  Inorganic fertilizer and cattle manure management for dry land maize production under low input conditions.  M.Phil Thesis, University of Zimbabwe. 170 pp.

Murwira, H.K. and  Kirchmann, H. 1993.  Nitrogen dynamics and maize growth in a Zimbabwean sandy soil under manure fertilization.  Communications in Soil Science and Plant Analysis 24:343-359.

Schleich, K. 1986.  The use of cattle dung in agriculture.  Natural Resources and Resource Development  23:53-87.

©1999, African Crop Science Society

The following images related to this document are available:

Photo images