J. Agronomy & Crop Science 172, 62—68 (1994)© 1994 Paul Parey Scientific Publishers, Berlin and HamburgISSN 0931-2250

Faculty of Agriculture, University of Peradeniya, Peradeniya, Sri Lanka

Growth, Yield and Nodule Activity of Phaseolus vulgaris L.as Affected by Soil Moisture

U. R. SANGAKKARA

Author's address: Dr. U. R. SANGAKKARA, Faculty of Agriculture, University of Peradeniya, Peradeniya, SriLanka.

Witb 4 tables

Received August 11, 1992; accepted Marcb 4, 1993

Abstract

A study evaluated the response of two varieties of beans {Phaseolus vulgaris L.) to different soil moisturelevels dunng a dry season. The soil moisture regimes maintained throughout the growth period were fieldcapacity, 70—75 %, 50—55 % or 20—25 % available soil moisture.

Plant growth, yield and nodulation were optimal when plants grew at high soil moisture levels. Withincreasing stress, all measured parameters of both varieties were reduced. However, polebeans, with its vinetype of growth was affected to a greater degree than bushbeans. In contrast, nodulation and nodule activity ofboth variables was affected by moisture stress.

A second experiment evaluated the effects of different soil moisture levels over the growth cycle ofbushbeans, which produce greater yields under drier conditions. The highest yields were obtained at highermoisture levels throughout the growth cycle. Moisture stress upto flowering reduced yields to a greater extentthan when the plants were subjected to reduced soil moisture after flowering appearance. Some casualmechanisms of the results of the experiments and possible implications for incorporating this popularvegetable legume in rainfed agricultural systems are presented.

Key words: Beans, Pbaseolus, soil moisture, growth, yield, nodule activity.

Introduction

Food legumes of the tropics and subtropics areprimarily grown in developing countries withagriculture based economies. In Asia, thesecrops are typically grown in small farms, undersubsistence conditions, in essentially cerealbased farming systems (WOOD and MYERS

1987). While most food legumes are grown fortheir seed, beans {Phaseolus vulgaris L.) isgenerally grown in Asia for its fresh tenderpods, which is consumed as a green vegetable.It also can be considered a very popular vege-table and major source of protein for a largeproportion of the population. It also has a highincome generating ability due to its populatingin urban areas (SILBERNAGEL et al. 1991).

Beans are generally cultivated as compo-nents of rainfed, small farming systems in Asia(PARATHASARATHY 1986). This is due to its rela-tively short growth season in contrast to othervegetables. This crop is also included as catchcrops in seasons of major crop failure, in orderto utilize any residual moisture (PATANOTHAI

and ONG 1987).Due to the inclusion of beans in most rainfed

farming systems, a major limiting factor for itssuccess is water stress (WHITE and SINGH 1991).This affects yields significantly, as beans withits short growth period, cannot withstand longperiods of water stress (HEDGE and SIRINIWAS

1989). Furthermore, research (e.g. MAURER etal. 1969, SMITH et al. 1988) illustrate that water

U.S. Copyright Clearance Center Code Statement: 0931-2250/94/7201-0062$10.00/0

Growth, Yield and Nodule Activity of Pbaseolus vulgaris L. 63

Stress due to drought or erratic rainfall resultsin reduced leaf, flower and pod yields and alsonodulation and nodule activity.

Studies on the importance of water stress onproductivity of beans as been extensively re-ported from the temperate world using singlevarieties (e.g. SMITH et al. 1988). However, inthe tropics beans are grown for pods either asvines or bushes, (pole or bushbeans) depend-ing on the time of planting, land, water availa-bility and farmer preference. Thus water stresscan affect these two forms of growth differ-ently as suggested for faba beans by PILBEAM etal. (1992). The influence of water on growthand yields and nitrogen fixation in beans canalso vary in relation to the time of stress.Studies (e.g. DUBETZ and MAHALLE 1969) reportthe importance of adequate water at flowering,while others (e.g. WORKAHEYU 1990) suggestthat adequate soil moisture is required durmgthe vegetative phase. Due to these variations instudies and the lack of sufficient data on theinfluence of water stress on productivity ofbeans in the humid tropics, studies were con-ducted to determine the effect of differentlevels of soil moisture on growth and noduleactivity of pole and bush types of beans.

Materials and Methodology

Experiment 1

A field study designated as a Randomized BlockDesign with four replicates per treatment, was car-ried out at the Experimental station of the Universityof Peradeniya, Sri Lanka, situated at Kundasale(9°N, 81°E; 410 m above sea level) during the dis-tinct dry period lasting from July—August.

The soil of the site, Ultisol had the followinggeneral characteristics —

Texture — Clay loan; pH — 6.54 + 0.24

Total N

ExchangeableK

0.12 % -h 0.02; Available P —26.40 + 2.14 ppm;28.02 + 3.11 ppm; and aC E C of 25.12 + 1.90 m.eq/100 g of soil. The water con-tent at field capacity was 21.84+ 1.22 %.

The varieties selected for the study were Wade(50—60 day, bush type) and Kentucky WonderGreen (60—70 day, pole type). The soil moistureregimes maintained throughout the growth period

were field capacity (Ml), 70—75 % of availablemoisture (M2), 50—55 % of available moisture (M3)and 20—25 % of available moisture (M4). Thesemoisture regimes were maintained by determiningsoil moisture gravimetrically at 2—3 day intervalsand adding the required water. The low quantum ofrainfall over the experimental period and high panevaporation (Table 1) enabled the successful comple-tion of the study. The time interval between soilmoisture determinations was based on the reported(DUBETZ and MAHALLE 1969) lack of adverse effectsof short periods of moisture stress on productivity ofbeans.

Plots of dimensions 2 X 4 m were separated by40 cm wide drains to avoid lateral movement ofapplied water. The dry soil was well prepared andsoil moisture regimes developed by application ofthe required quantity of water.

Uniform seeds of the selected varieties (Germina-tion 95.2 -I- 1.23) were soaked for 12 hours indistilled water and planted at a spacing of 25 x 30 cmin the prepared plots. Basal fertilizer applicationequivalent to 20 kg N, 50 kg P205 and 50 kg K20per has was applied to all plots. Hand weeding wascarried out at 10 and 20 days, and a prophylacticinsecticide (Sumithion 40 % EC) was sprayed soonafter weeding.

Experiment 2

A pot trial designed as a Completely RandomizedDesign with five replicates was carried out at theUniversity experimental station using the same soildescribed in experiment 1. Pots with dimensions30 cm (diameter) and 40 cm (height) were filled with3 kg of sieved soil, and the weight of pots with soil atfield capacity determined.

The treatments of this study were maintenance ofsoil moisture at —

90—100 % of available soil moisture from plant-ing to harvest (Al)

90—100 % of available moisture from planting toflowering and 30—40 % thereafter{A2)

30— 40 % of available soil moisture from plant-ing to flowering and 90—100 %thereafter (A3)

30— 40 % of available soil moisture from plant-ing to harvest (A4)

Uniform seeds (germination 94.5 -I- 1.33 %) of thebush type (Variety Wade) were soaked overnight,planted at a rate of 3 per pot, and soil moisturemaintained as per treatments by weighing the pots atthree day intervals. Each treatment consisted of 8pots per replicate.

The rates of fertilizer and crop management wereas per Experiment 1.

64 SANGAKKARA

Measurements

Establishment, dry matter accumulation upto flowerappearance of plants by harvesting three plants perplot at 5 day intervals, days to flower appearance,flowers per plant, percentage pod set and yield offresh pods per plant were determined. The dryweights were used to calculate relative growth rates(g/g/wk) as per method of HUNT (1978). In addition,four plants per plot were carefully uprooted in Ex-periment 1, and nodule numbers and their activity(Acetylene reduction) determined by the techniqueof HARDY etal. (1968).

Table 1. Selected climatic parameters over the experi-mental period

Climatic parameter Data ± S.E.

Rainfall (mm) 27.2Mean daily temperature (°C) 29.8 ±1 .7Mean daily RH (%) 71.04 ± 3.47Mean pan evaporation (mm/day) 4.04 ± 0.07Day length (hours) 10—11

Results and Discussion

The climate during Experiment 1 was warmand dry (Table 1). This provided a good envi-ronment for the study and was consistent withnormal rainfall patterns of the season. Evap-oration exceeded the rainfall received, and thusplants wilted if no supplementary irrigationwas provided. The rainfall received (27 mm)

which was distributed throughout the periodmade no impact on the soil moisture levels,and thus was not considered in the study.

Moisture at planting is a prerequisite forvegetable production (GOWDA et al. 1986). Thisis reflected in the data of this study (Table 2).However, the reduction in establishment isgreater (60 %) in polebeans than in bushbeans(47 %), when soil moisture is reduced to20—25 %. The greater sensitivity of polebeansis also reflected at the 50—55 % soil moisturelevel, where reduction in establishment is34 % when compared to 16 % in bushbeans.

The effect of moisture on relative growthrates (RGR) is greater than on establishment.Although polebeans have a higher RGR, de-pletion of soil moisture affects this variety to agreater extent. Thus, RGR of polebeans isreduced by 82 % in contrast to a reduction of60 % in bushbeans when soil moisture is re-duced to 20—25 %. A reduction of soil mois-ture to 70—75 % also affects RGR of pole-beans to a greater degree. This illustrates thegreater sensitivity of this variety to water stressduring early growth. The study also suggeststhat vegetative growth of both varieties is moresensitive to moisture stress than establishment,which could be attributed to the requirementof water for photosythesis and trans location.

The lack of water induces early flowering.inbeans (Table 2). The stress caused by lack ofsufficient water could develop imbalances inthe plant thus inducing flowering. Again, the

Table 2. Effect of soil moisture on vegetative growth and yield parameters of beans

Type

PoleBeans

Sx

BushBeans

LSD(P

Moisture'-'level

MlM2M3M4

MlM2M3M4

= 0.05)

Establish-ment

98.496.564.838.615.96

97.898.481.450.4

8.65

RGR^̂ =̂(g/g/wk)

0.18230.10260.06420.03260.0021

0.15690.12720.08120.6180.0014

Days toflowering

37393332

1.98

29312828

0.84

Flowers/plant

383418122.11

272518102.45

% Podset

79684226

86815948

Yield/plant (g)

144.2104.855.726.423.98

122.4101.666.940.711.42

Soil moisture levels Ml, M2, M3 and M4 represent field capacity, 70—75 %, 50—55 % and 20—25 % ofavailable soil moisture throughout the growth cycle of the crop.RGR (g/g/wk) is calculated from day weight (g) per plant from germination upto flowering.

Growth, Yield and Nodule Activity of Pbaseolus vulgaris L. 65

effect of water stress on this parameter is lessevident in the busy type.

Flowering of the selected varieties of beans isgreatly affected by water stress, confirmingresults of HEDGE and SIRINIWAS (1989). How-ever, there are differences in the two varieties.Polebeans, which produces a greater numberof flowers, is affected more by water stress(e.g. 68 % when compared with 62 % in thebush type when soil moisture is reduced to20—25 %) . However, due to the lowernumber of flowers in bushbeans, polebeanshave a greater number at the lowest level of soilmoisture.

Soil moisture affects pod set in both varie-ties. Bushbeans produces a greater numbers ofpods from flowers at all moisture levels. Thus,although this variety has a lower number offlowers, it overcomes this setback to producemore pods per plant than polebeans. This illus-trates its adaptability and tolerance to dry con-ditions.

An evaluation of the data on reduction inpod set also illustrates the greater susceptibilityof polebeans to moisture stress.

Yields per plant follow the responser ofyield components to moisture levels. Althoughpolebeans have higher yields at field capacity(an increase of 18 %), the relative advantage isremoved with a 25 % reduction in soil mois-ture. Thus, at very low soil moisture levels,

bushbeans yields exceed those of polebeans by50 %.

Analysis of the correlations between growthand yields produce significant positive rela-tionships in both varieties (r = 0.781''" in pole-beans and r = 0.877'-"^ in bushbeans). Thisalso shows a close relationship between vegeta-tive growth and yields of bushbeans. The low-er correlation in polebeans, although signifi-cant, indicates greater variations m yield com-ponents, which can affect per plant produc-tion.

The influence of depleting soil moisture onnodule numbers and activity is well demon-strated in most food legumes. This phenome-non is shown in beans grown for pods(Table 3), which are considered poornodulators although they accumulate similarquantities of nitrogen as other grain legumes(SMITH et al. 1988). Polebeans, with its largerplant form has a greater number of nodules inall treatments. However, the reduction innodule numbers die to moisture stress is simi-lar in each variety at both samplings (i.e.7A—75 % and 66 % in the first and secondsampling respectively).

Acetylene reduction (ARA) is reduced bymoisture stress in both varieties (Table 3).However, the rate of reduction due to mois-ture stress is lower in bushbeans. In bothvarieties, the rate of reduction in ARA is great-

Table 3. Effect of soil moisture on nodulation and nodule activity of beans

Type Moisture* '̂ level Nodulation and ActivityAt 25 days At flower initiation

Nodules/ ARA (^M Nodules/ ARAC2H4/plant/Hr)plant plant

PoleBeans

Sx

BushBeans

Sx

MlM2M3M4

MlM2M3M4

393822104.2

24221483.1

21.918.110.34.64.12

18.516.39.55.12.96

484324123.0

363220124.10

36.330.517.15.34.19

32.028.314.36.52.15

=̂ Soil moisture levels Ml, M2, M3 and M4 represent field capacity, 70—75 %, 50—55 % and 20—25 % ofavailable soil moisture throughout the growth cycle of the crop.

J. Agronomy 8c Crop Science, Vol. 172 (1)

66

Table 4.

Moisture

Relationship between

level Establish-ment (%)

soil moisture

RGR(g/g/wk)

, growth and

Days toflowering

yield parameters in bush

Flowers/plant

Podsplant

beans

% Podset

SANGAKKARA

Yield/plant (g)

AlA2A3A4LSD (P = 0.05)

92948891

7.14

0.12660.11950.07420.6980.0015

313328273.8

173121232.1

IIJ18.015.59.73.64

84587442

115.884.866.558.49.88

Moisture levels correspond to —

Al = 90—100 % of available soil moisture during crop growth.A2 = 90—100 % of available soil moisture upto flowering and 30—40 % thereafter.A3 = 30—40 % of available soil moisture upto flowering and 90—100 % thereafter.A4 = 30—40 % of available soil moisture during crop growth.

er at flowering appearance, which could beattributed to the stress placed upon the plantby the lack of water at the inception of repro-ductive growth.

The activity of nodules (i.e. ARA/noduIenumbers) in bushbeans is greater. This suggestthat although nodulation and activity are af-fected to similar extents by water stress, whichmay be due to the accumulation of proline innodules, as suggested by KOHL et al. (1991),nodule activity of bushbeans is greater in alltreatments. Thus further studies on the effi-ciency of nodules in these two important typesof vegetables beans in the tropics is warranted.

Experiment 2

Bushbeans respond differently to the adoptedwater stress treatments (Table 4). Establish-ment of beans is not reduced in all treatments.The presence of 30—40 % of available water atplanting seems adequate for establishment ofthis species, although Experiment 1 suggeststhat depletion levels to 20—25 % of availablewater reduces establishment. The confined en-vironment of the pot which should retain wa-ter unlike the field, could be considered thecasual factor, although the greater ability ofbushbeans to overcome water deficits at plant-ing needs further study.

Plant growth of bushbeans declines withwater stress. However, availability of adequatesoil water over the vegetative phase results insimilar RGR values to those obtained whenbushbeans are grown at 90—100 % of avail-able water throughout the growth period. In

contrast, reduction of soil moisture by50—60 % at planting reduces RGR by 42 %.

Days to flower initiation is reduced by lowersoil moisture levels in the early growth phase,thus confirming results of Experiment 1.However, flowers per plant is greatest whensoil moisture levels are high either throughoutthe growth phase or during early stages.

Pod set IS also affected by lower soil mois-ture levels.

Availability of adequate soil moisturethroughout the growth period ensures a higherpercentage of pod set due to lower abscission.Overcoming low levels of soil moisture a'fierflowering also increases pod set. Moisturestress after flowering or throughout thegrowth period affects pod set significantly,primarily due to flower abscission.

The effect of moisture stress at differentstages of growth in bushbeans is best shown inthe yield data. Again, a positive correlation(r = 0.861''"'") was established between vegeta-tive growth and yields. Yields are highest whenplants have sufficient moisture, thus illustrat-ing the requirement of adequate water for op-timum production. However, maintenance ofadequate moisture upto flowering, which ap-proximately covers half the lifespan of the cropproduces a greater yield than when sufficientwater is available only after flowering. This isprimarily due to greater vegetative growth andflower numbers, which can offset setbacks oflower pod set. However, as other studies (e.g.MAURER et al. 1969) report a greater reductionin yields when beans are subjected to waterstress after flowering this requires further

Growth, Yield and Nodule Activity of Phaseolus vulgaris L. 67

clarification under field conditions in thetropics. The lack of adequate soil moisturethroughout the growth period reduces yieldsby 40 %, when compared with reductions of45 % and 26 % when soil moisture is re-stricted before and after flowering.

Farmers in the tropics plant beans underrainfed conditions primarily in the drier sea-sons, as principal crops such as cereals orlongterm grain legumes occupy the wet season(WOOD and MYERS 1987). Thus beans can besubjected to erratic rainfall. The study showsthat polebeans, which have indeterminategrowth patterns is more suitable for situationsof adequate soil moisture. In contrast, bush-beans, with its shorter deterministic growthcycle is less susceptible to soil moisture stress.However, greater quantities of fertilizer nitro-gen may be required for this low nitrogenfixing species under conditions of moisturestress as nodulation und nodule activity ofboth varieties are similarly affected.

Planting of beans under dry conditions withthe anticipation of rainfall towards the latterpart of agricultural seasons causes greater yieldreduction than when subjected to dry periodsat later stages. Thus establishment of beansafter a crop to utilize residual soil moisture asin rice based farming systems could yieldgreater harvests than when the crop is plantedat the onset of the season, before rains. Underthe conditions where irrigation is not availablefarmers could obtain greater yields by plantingpolebeans is sufficient rainfall is expected.Under conditions of doubt on the availabilityof soil moisture, bushbeans are considered thebest alternative to obtain a harvest with limitedwater in a short period of time.

Zusammenfassung

Wachstum, Ertrag und KnoIIchenaktivitatvon Phaseolus vulgaris L. in Abhangigkeitvon der Bodenfeuchtigkeit

In einer Untersuchung wurde die Reaktionvon zwei Bohnensorten {Phaseolus vulgaris L.)gegenliber unterschiedlicher Bodenfeuchtig-keit wahrend der Trockensaison untersucht.Die Bereiche der Bodenfeuchtigkeit wurdenwahrend der Wachstumsperiode bei Feldka-pazitaten von 70—75 %, 50—55 % bzw.20—25 % verfiigbarer Bodenfeuchtigkeit ge-

halten. Pflanzenwachstum, Ertrag und KnoU-chenbildung waren optimal unter hohen Bo-denfeuchtigkeitsbedingungen. Mit zunehmen-dem Stref5 wurden alle untersuchten Parameterder beiden Sorten reduziert. Allerdings Stan-genbohnen mit kletterndem Wachstumsverhal-ten waren starker beeintrachtigt als Buschboh-nen. Im Gegensatz dazu war die KnoUchenbil-dung und die KnoIIchenaktivitat in beiden Ty-pen durch Feuchtigkeitsstrefi beeintrachtigt. Ineinem zweiten Experiment wurden die Wir-kungen unterschiedlicher Bodenfeuchtigkeits-verhaltnisse auf den Wachstumsverlauf vonBuschbohnen, die einen hoheren Ertrag unterTrockenbedingungen erbringen, untersucht.Die hochsten Ertrage wurden im Bereich derhoheren Feuchtigkeitskonzentrationen wah-rend des Wachstumszyklus gefunden. Wasser-streE bis zum Beginn der Blute reduzierte dieErtrage in einem grofSeren Ausmaf̂ als beieiner Verringerung der Bodenfeuchtigkeit nachdem Erscheinen der Bliiten.

Acknowledgements

Gratitude is expressed to Messrs A. DE SOYZA andMs N. S. WlJESINGHE for research assistance.

References

DUBETZ, S., and P. S. MAHALLE, 1969: Effect ofwater stress on bushbeans (Pbaseolus vulgaris) atthree stages of growth. Journal of the AmericanSociety for Horticultural Science 94, 479—481.

GOWDA, P. M., K. T. SHIVASAHNKER, and P. J.

MATHAI, 1986: Principles of vegetable production.In: T. K. BOSE and M. G. SOM (eds.), VegetableCrops in India, 42—90. Naya Prokash, Calcutta,India.

HARDY, R. W . F., H . D . HOLSTEIN, E. K. JACK-

SON, and R. C. BURNS, 1968: The acetylene-ethyl-ene assay for nitrogen fixation — Laboratory andfield evaluation. Plant Physiology 43, 1185—1207.

HEDGE, D . M. , and K. SIRINIWAS, 1989: Effect ofirrigation and nitrogen on growth, yield and wateruse efficiency of french bean. Indian Journal ofAgronomy 32, 180—184.

HUNT, R. , 1978: Plant growth analysis. EdwardArnold, UK, 67 pp.

KOHL, D . H . , E. J. KENNELLY, Y. ZHU, and K. R.

SCHUBERT, 1991: Proline accumulation, nitrogen-ase (C2H2 reducing) activity and activities of en-zymes related to proline metabolism in droughtstressed soyabeans. Journal of ExperimentalBotany 42, 831—873.

68 SANGAKKARA, Growth, Yield and Nodule Activity of Phaseolus vulgaris L.

MAURER, A . R., D . R. ORMROD, and N. J. ScOTT,1969: Effect of five soil water regimes on growthand composition of snapbean. Canadian Journal ofPlant Science 49, 271—278.

PARATHASARATHY, V. A., 1986: French beans. In:T. K. BOSE and M. G. SOM (eds.), VegetableProduction in India, 497—514. Naya Prokash,Calcutta, India.

PATANOTHAI, A . , and C. K. O N G , 1987: Limitsimposed by management in rainfed farming sys-tems. In: E. S. WALUS and D. E. BYTHE (eds.),Food Legume Improvement for Asian FarmingSystems, 72—82. ACIAR Publication 18, ACIAR,Australia.

PiLBEAM, C. I., J. K. AKATSE, E . D . HEBBLETH-

WAITE, and S. D. WRIGHT, 1992: Yield productionin two contrasting forms of spring sown fababeansin relation to water supply. Field Crops Research29, 273-287.

SiLBERNAGEL, M. ] . , W. JANSSEN, J. H. C. DAVIES,

and G. M. DE OGA, 1991: Snapbean production inthe tropics. In: A. VAN SGHOONHAVEN and O.VOYSET (eds.). Common Beans — Research for

Crop Improvement, 835—862. CIAT, Columbiaand CAB International, UK.

SMITH, L., M . DIJAK, and D. J. HUME, 1988: The

effect of water deficit on nitrogen (C2H2) fixationby white bean and soyabean. Canadian Journal ofPlant Science 68, 957—967.

WHITE, S. P., and S. P. SINGH, 1991: Breeding foradaptation to drought. In: A. VAN SCHOONHOVEN

and O. VOYSET (eds.), Common Beans — Researchfor Crop Improvement, 501—560. CIAT, Colum-bia and CAB International, UK.

WORKAHEYU, T., 1990: Effect of sowing date andfertihzer on grain yield of haricot bean {P. vul-garis). In: J. B. SMITH (ed.). Workshop on BeanResearch in Eastern Africa, 330—333. Nairobi,Kenya.

WOOD, I. M., and R. J. K. MYERS, 1987: Foodlegumes in farming systems of the tropics andsubtropics. In: E. S. WALLIS and D. E. BYTHE

(eds.). Food Legumes Improvement for AsianFarming Systems, M—45. ACIAR Publication 18,ACIAR, Australia.