TY  - BOOK
AU  - Ayisha, V V
AU  - Rajalekshmi, K (Guide)
TI  - Soil test crop response studies in cluster bean (Cyamopsis tetragonoloba L.) in lateritic soils of Kerala 
U1  - 631.4 
PY  - 2021///
CY  - Vellanikkara 
PB  - Department of Soil Science and Agricultural Chemistry, College of Agriculture
KW  - Soil Science and Agricultural Chemistry
KW  - Bean
KW  - Cyamopsis tetragonoloba L
N1  - M Sc
N2  - Cluster bean, commonly known as guar, is a legume crop cultivated as a 
vegetable, green manure and forage crop. India is the leading producer of cluster bean in 
the world and accounts for around 80 per cent of global production. The generalised 
application of fertilizers by farmers result in under or over fertilization, lowering 
production and profitability while also polluting the environment. So the emphasis on soil 
test based balanced fertilizer recommendation has become more pertinent in the current 
scenario of high fertilizer costs and yield maximisation programmes. Hence, the 
investigation entitled “Soil test crop response studies in cluster bean (Cyamopsis 
tetragonoloba L.) in lateritic soils of Kerala” was undertaken.
The study was conducted at College of Agriculture, Vellanikkara in lateritic soils 
(Ultisol) in the STCR field during 2020-2021 with the objective of developing soil test 
based fertilizer prescription equation for cluster bean using inorganic fertilizers alone and 
with the combined use of organic manures.
A fertility gradient experiment was conducted to create soil fertility gradient in the 
field by applying graded doses of N, P and K fertilizers and raising fodder maize var. CO1. After the development of fertility gradient, the main STCR experiment was conducted 
in the same field with the test crop, cluster bean var. Pusa naubahar. The treatment 
structure consisted of four levels of nitrogen (0, 10, 20 and 40 kg ha-1
), four levels of 
phosphorous (0, 30, 60 and 120 kg ha-1
) and four levels of potassium (0, 40, 80 and 120 
kg ha-1
) along with three levels of FYM (0, 15 and 25 t ha-1
). The basic parameters such 
as nutrient requirement (NR) and contributions of nutrients from soil (CS), fertilizer (CF) 
and FYM (COM) were computed from the field experimental data.
The nutrient requirements (NR) for cluster bean were worked out as 0.68, 0.05
and 0.22 kg N, P2O5 and K2O to produce one quintal yield. The contributions from soil
(CS) were estimated as 9.84, 2.29 and 1.99 per cent of N, P2O5 and K2O respectively. The 
contributions from fertilizer (CF) were calculated as 90.90, 3.29 and 10.82 per cent and 
that from FYM (COM) were 7.17, 1.92 and 2.96 per cent for N, P2O5 and K2O 
respectively.
From the above basic data, fertilizer prescription equation for specific yield
targets of cluster bean in the lateritic soils were derived as follows,
NPK alone: 
FN = 0.74*T - 0.11*SN
FP2O5 = 1.47*T – 1.59*SP 
FK2O = 2.05*T- 0.22*SK 
NPK + FYM (IPNS)
FN = 0.74*T - 0.11*SN – 0.08*ON
FP2O5 = 1.47*T – 1.59*SP – 1.34*OP
FK2O = 2.05*T - 0.22*SK – 0.33*OK
Where, FN, FP2O5 and FK2O = Fertilizer N, P2O5 and K2O in kg ha-1
T = Yield target in q ha-1
SN, SP and SK = STV for available N, P and K in kg ha-1
.
ON, OP and OK = Amount of N, P and K supplied through FYM in kg ha-1
.
The multiple regression model calibrated with yield as dependent variable and 
soil test results and inorganic fertilizer doses as independent variables had 62.5 per cent 
predictability. The yield of cluster bean increased with the application of NPK alone and 
IPNS viz. NPK plus FYM treatment and the magnitude of increase was higher under 
IPNS over NPK alone. 
The study is useful to adjust fertilizer doses based on yield target and available
resources of organic manure with the farmers. The equations developed for cluster bean 
should be tested in places with similar agro climate and soil situations for validation
UR  -  https://krishikosh.egranth.ac.in/handle/1/5810197468
ER  -