On-farm Evaluation of Sweet Sorghum Cultivars in Zimbabwe using

Participatory Approaches to Understand Farmers’ Trait Preferences and

Cropping Systems

M. Mativavarira1*, E. Mwenje2, A. Van Rooyen3, B.M Jumbo3, G. Sisito4, J. Dimes5

1Crop Breeding Institute, Sorghum and Millets research unit, Matopos Research

Station Bag K 5137, Bulawayo, Zimbabwe, 2 National University of Science and

Technology, P.O Box AC 939, Ascot, Bulawayo, Zimbabwe, .3 ICRISAT-Bulawayo,

P.O Box 776, Bulawayo, Zimbabwe, 4 Matopos Research Institute, Bag

K5137,Bulawayo, Zimbabwe, 5 DEEDI, P.O Box 102 Toowoomba, QLD 4350,

Australia, .*Author for correspondence; mmativa@yahoo.com

SUMMARY

Participatory rural appraisals (PRAs) and Participatory variety selection (PVS)

methods were used to understand cropping systems, important sorghums traits and

famers preferred sweet sorghum cultivars in Zimbabwe. The ranking of field crops

grown by smallholder farmers by order of importance were maize, sorghum,

cowpeas, pearl millet and groundnuts. Among the sorghum varieties grown by

farmers only two improved sorghum varieties were common among farmers and

these were the white grained SV-1 and red grain DC75. Drought tolerance, pest

resistance, diseases resistance and early maturity were important sorghum traits. In

particular bird resistance was considered very important for pest resistance. Among

the sweet sorghum cultivars Seredo was the preferred variety as it has shown to

have water stress tolerance during the vegetative stage, is red grained hence bird

resistant, can be used for thick porridge and beer brewing. Preliminary analysis has

shown that this variety has also high sorghum diastatic units of 39.6 units and high

milling yields. Our result shows that participatory variety selection is an important tool

for cultivars evaluation and sweet sorghum cultivars have great potential to meet

food and feed requirements for crop –livestock farmers in Zimbabwe.

INTRODUCTION

Sorghum [Sorghum bicolor (L.) Moench] is the principal dryland nutritional coarse

cereal grown for food, feed, fodder and fuel around the world (FAO 2004). It is water

efficient (Almodares , et al., 2008), drought resistance (Tesso et al., 2005) and with

a high yield of biomass (Almodares , et al., 1994).It is often grown in areas of low

fertility and unpredictable rainfall (Van-Oosteroma et al., 2001).

Farmer participatory approaches for the identification or breeding of improved crop

cultivars can be usefully categorized into participatory varietal selection (PVS) and

participatory plant breeding (PPB) (Joshi. and Witcombe. 1996). Participatory

varietal selection (PVS) is the selection by farmers of finished or near-finished

products from plant breeding (Joshi. and Witcombe. 1996). These include released

cultivars, varieties in advanced stages of testing and well characterised material

such as advanced experimental lines. Generally participatory variety selection (PVS)

is a more rapid and cost effective way of identifying farmer-preferred cultivars if a

suitable choice of cultivars exists. If this is impossible, then the more resource-

consuming participatory plant breeding (PPB) is required (Joshi. and Witcombe.

1996).

Witcombe et al. (1996) found that in many developing countries, most cultivars

grown by farmers are old and only a few of the released cultivars are grown widely.

The reasons, among others, include inadequate exposure to new varieties, despite

the occasional presence of suitable ones, or the varieties are not adequate to satisfy

farmers’ needs. This is because plant breeders and farmers often differ in their

perspectives. While breeders seek cultivars with broad adaptation, and often prefer

to release only one or a few cultivars at a time to facilitate seed production and

distribution, farmers might favour a variety of cultivars to address different niches on

their farm or in their production system.

The collaboration between ICRISAT, ILRI and the Department of Research and

Specialist Services (DRSS), lead to the importation of sweet sorghum cultivars for

evaluation in Zimbabwe. This study was implemented with crop-livestock farmers to

understand sorghum trait preferences, current cropping systems and sorghum

varieties grown by farmers.

MATERIALS AND METHODS

The study area: Nkayi District

Nkayi is one of the six districts located in Matabeleland North Province in the

southwestern part of Zimbabwe (Figure 1). Historically, Nkayi District was largely

uninhabited and sparsely populated due to its low agricultural potential. Currently,

Nkayi is a relatively densely populated district with around 40 persons km-2 (Central

Statistics Office, 1992). This is due to the initial settlement patterns and population

growth. In recent years, this pressure has resulted in wide ranging land use changes

mostly dominated by the expansion of arable plots into forest and grazing areas.

Nkayi district has a mixed crop livestock land use system and it is in the semi arid

tropics characterized by poor and erratic rainfall that ranges from 450-650 mm per

annum and suitable for semi extensive livestock production (Vincent and Thomas.,

1961). The potential for cropping is however limited in this area with also poor soil

fertility as the soils are sandy to sand-loam.

Study methods: Participatory rural appraisals

The purposive sampling strategy was used to select four wards in different areas two

villages (Mhutshapansi and Silindeni) were selected from the northern part, while the

other two villages (Menda and Nkunzini) were southern part of the district. In each

ward, one village was randomly selected. In each village a PRA workshop was

conducted with a minimum of 40 participants drawn from community leadership,

including traditional leaders, leaders of community institutions such as churches,

traditional healers, and leaders of farmer associations and representatives of

women’s groups. A team of six researchers conducted the PRAs, dividing the

responsibilities of facilitating (two), note taking (two) and observing the discussions.

Extension workers participated as observers in focus group discussions.

Participatory rural appraisals (PRAs) were conducted to know the crops grown,

sorghums varieties grown by farmers, and important sorghum traits. A number of

PRA tools were used such as ranking, pairwise scoring and ranking and matrix

ranking. Different crops grown by farmers were ranked for their importance in

meeting household food and feed security. The common traits of the currently grown

sorghum cultivars were also discussed in focus group discussions. The pairwise

scoring and ranking was also conducted for important sorghum traits in group

meetings.

Participatory variety selection (PVS)

Eighteen sweet sorghum cultivars from the International Crops Research Institute for

the Semi-Arid Tropics (ICRISAT)-India, two released varieties in Zimbabwe and

farmers varieties were grown in farmers fields in the 2009/10 season to assess them

for different traits using matrix ranking. These sweet sorghum cultivars were once

evaluated for farmers preferences in on-station trials in the 2007/08 season

(Mativavarira et al., 2011) hence the on-farm were made to verify their performance

in farmer’s environments. Twenty farmers (10 male and 10 female farmers) were

involved in this study these were from the four different wards in Nkayi (Figure 1).

Laboratory quality tests

The grain samples from one trial was harvested and evaluated for sorghum diastic

units (SDU) and grain hardness score. The SDU tests were done to evaluate the

potential for use in brewing, while grain hardness score would give results for

potential use in brewing, livestock feed and flour yield.

Data analysis

The ranking data was analysed by excel to find mean ranks for each trait by male,

female farmers and their combined average. The data was coded, entered in SPSS

and analysed through descriptive statistics using the frequencies and cross-

tabulation procedures. Chi-square was used to measure any significant differences

in ranking for traits by all farmers, male and female farmers using SPSS version

13.0.

RESULTS

Crops and sorghum varieties grown

The first four important crops grown in these areas are maize, sorghum, cowpea and

pearl millet (Table 1). The common maize varieties were mainly short season

cultivars like SC 400 series which are grown to supply early food supply, while on

sorghum the common varieties are SV-1, DC 75, Tsveta and Red swazi (Table 2).

The most common uses of sorghum were food (sadza), beer brewing, and feed for

chickens and livestock. Sweet sorghum is also grown in this area to quest thirst while

working in the fields and has a commercial value where it is sold at road sides.

Among the four released sorghum varieties only SV-1 is known by farmers. SV-1

was the first released sorghum variety in Zimbabwe in 1987, it’s an early maturing

variety, creamy white grained, semi-dwarf, and has excellent milling quality hence

good variety for food. This variety together with Tsveta are attacked by birds and the

whole crop will be destroyed if birds are not scared, hence Red swazi and DC 75

are options for farmers as they are not usually attacked by birds.

Fig 1. Map of Zimbabwe Showing Nkayi Test Location.

Table 1: crops grown by farmers in Nkayi ranked in order of importance.

Crop rank

maize 1

sorghum 2

cowpeas 3

pearl millet 4

vegetables 5

groundnut 6

sweet potatoes 7

sunflower 8

okra 9

Ranking Sorghum Traits in order of Importance based on Smallholder Farmers

Opinion.

The pairwise ranking results showed that drought tolerance and pest resistance in

sorghum production are important traits according to farmers (Tables 3 and 4). The

need for drought tolerant cultivars is due to the increase in occurrence of mid and

end of season droughts and reduced amount of rainfall received in this years. The

major pests in sorghum production in Zimbabwe are qualea birds. Diseases

resistance and maturity were considered third in importance but farmers could not

mention any diseases they know, while on maturity they mentioned the need for

early maturing cultivars comparable to SV-1. The need for high grain yield would be

considered after the cultivars are shown to be drought tolerant and bird resistant as

farmers would not get good grain yield due to those constraints.

Table 2: Characteristics of sorghum varieties grown by farmers in Nkayi.

Characteristics Disadvantage

Sv-1 -Early maturity

-Good flour for food

-Tolerance to weevils

-Seed can be recycled

-water requirement is low

-high bird attack

-when planted early affected by grain

rots

Tsveta -high grain yield when

planted early

-food and beer

-strong stover

-high bird damage as it matures at

different stages

- water requirement high

Red swazi -multiple harvest when

planted early

-bird resistance

-strong stover

- not good for food its sour needs

dehulling (red grained)

-water requirement low

DC 75 -multiple harvest when

planted early

-bird resistance

-strong stover

-water demand is medium

Participatory variety selection

The male farmers rankings on maturity showed preferences on; SV-4, Macia, FV-1,

E36-1, SPV 1022, SPV 1411, and CSV15. While female farmers selected PVK801,

NTJ2, JJ1041, S35 and FV-1(Table 5) and these cultivars generally matures in 110 –

125 days hence they are in early and medium maturity classes. Stem sweetness

results showed that any cultivar with Brix reading of above 10 % are considered

sweet by male farmers, while female farmers mean rankings showed that any Brix

reading of above 13 % was considered as good for stem sweetness. Both male and

female farmers had preference for white grained cultivars. The overall preferences

for male farmers was on white (Macia, SPV 1022, SPV 1411) and red (MSS,

Seredo) grained cultivars while female farmers was on red grained cultivar Seredo.

There were significant difference (p<0.05) on cultivars ranking for maturity, stem

sweetness and grain colour based on farmers selection criteria used (Table 6). Male

farmers ranking shows significant differences (p<0.05) for maturity and stem

sweetness, while no significant differences were observed for grain colour as they

also have preferences for red grained cultivars which are used in beer brewing.

Table 3: Pairwise scoring and ranking of important sorghum traits for food and fodder

in production in semi arid environments of Nkayi.

Grain

yield

Stover

yield

Plant

height

Maturity

period

Grain

colour

Drought

tolerance

Diseases

resistance

Seed

quality

Pest

resistance

Pest

resistance

PR PR PR PR PR DT PR PR -

Seed

quality

GY SQ PH MP GC DT DR - PR

Diseases

resistance

GY DR DR DR DR DT - DR PR

Drought

tolerance

DT DT DT DT DT - DT DT DT

Grain

colour

GC GC PH MP - DT DR GC PR

Maturity

period

MP MP MP - MP DT DR MP PR

Plant

height

GY PH - MP PH DT DR MP PR

Stover

yield

GY - PH MP GC DT DR SQ PR

Grain

yield

- GY GY MP GC DT GY GY PR

Table 4: Results of pairwise scoring and ranking results of sorghum important

traits

Ranking Trait

1 Drought tolerance

2 Pest resistance

3 Disease resistance/maturity period

4 Grain yield

5 Grain colour/ plant height

6 Seed quality

7 Stover yield

Among male selected cultivars, in on-station trials only SPV 1411 was further

selected in on-farm trials (Table 5). According to women preferences their selected

cultivars in on-station trials performed worst in on-farm trials (Table 5). The farmers

combined analysis on preferences shows no preferences for the on-station selected

cultivars but had preferences on Seredo (Table 7). Famers’ ranking for water stress

tolerance in vegetative growth stage, uses for food (sadza) and beer brewing, the

on-station selected, and released cultivars in Zimbabwe were comparable to on-

farm selected cultivar. On laboratory tests, among the most preferred cultivars in on-

station trials by male and female farmers, E36-1 and ICSR93046 had generally good

brewing quality. They also have grain hardness score of 3.0 (E36-1) and 4.0

(ICSR93046) hence are classified as intermediate and hard for grain hardness score

hence would give high milling yield. Stover yield was significantly different(P<0.05)

among cultivars with SPV 422 having significantly very high stover yield of 2000

kg/ha (Table 7). Seredo and SPV 422 outperformed other cultivars with over 1000

kg/ha (Table7) on grain yield.

Table 5: Men and women farmers mean ranking of sorghum cultivars in on-farm

trials in 2009/10 season in Nkayi.

Mal

e

female

VARIETY matur

ity

stem

sweetness

grain

colour

prefere

nces

maturit

y

stem

sweetness

grain

colour

fodder

preferences

preference

s

GD65195 3.5 2.6 3 5 3.7 2.8 3 3 5

ICSV700 3.5 2 3 5 3.5 2.8 3 5

SPV1022 1.25 2 1 1 4 3 4 5

SPV1411* 2 2.2 1 1 3 2.6 1 3 5

PVK801* 3.25 3 1 3 1 3.2 3.5 5

NTJ2 2.75 1.8 1 3 2 3 1 4 5

M SS 2.5 1 - 1 4.5 1 1 4.3

JJ1041 3.25 3.2 1 4 2 3.4 1 4 4

IS 19674 4.75 3.8 5 4 4.5 3.6 5 5

SEREDOF 2.25 3 3 1 3 2.8 3 2.5 2.3

B24 3.75 2.2 3 5 4 2.2 3 2 5

S35# 2.5 2.2 1 3 2 3.2 3 3.7

ICSV93046 3.75 2.4 1 2 5 2.6 3.5 5

ICSR93034# 3.5 2.4 1 3 3 2.8 4 5

CSV15 2 2 1 2 2.5 3.4 3.5 5

E36-1* 1.25 2.6 1 3 2.5 2.6 3 5

SPV422# 3 3.8 2 4 5 4.2 4 5

ICSV25263 2.5 3 4 3 3.7 3.2 4 3 5

MACIA 1.25 3.2 2 1 2.5 2.4 2.5 4

SV-4 1 3.4 1 2 3.5 2.2 3.5 3.7

FV1 1 3 1 1 3.3 1

FV2 1.5 4 2 3 4

Ranking was on 1-5 scale, where 1= the best, 5= the worst,*=male selected cultivars

in previous on-station trials, #=female selected cultivars in previous on-station trials,

F= farmers selected cultivars in on-farm trials.

Table 6: Chi-square analysis of farmer’s rankings for different traits.

maturity Sweet ness Grain colour

#Fodder

preferences

All cultivars * * * -

Sorghum type - - - NS

Male farmers * * NS -

Female

farmers NS NS NS

NS

* = Significantly different at P = 0.05, NS =not significantly different, -= not analysed

Discussion

Maize continues to dominate farmer’s crop preferences in the semi arid

environments compared to drought tolerant crops like sorghum and pearl millet

which agrees with previous findings by Twomlow et al (2006). The national sorghum

improvement programme in Zimbabwe has so far released four improved sorghum

varieties SV-1, SV2, SV-3 and SV-4 in the period 1987 to1998 (Mgonja et al., 2005)

but famers are only aware of the first variety, SV-1, implying limited diffusion of

improved varieties from breeders to farmers. This could be that varieties do not

satisfy famer’s needs or there is poor distribution and marketing or both factors might

be contributing to limited access to improved varieties.

Table 7: Grain and stover yield (kg/ha), sorghum diastatic units (SDU), Grain visual

hardness score (GHS) and mean ranking of sweet and released sorghum cultivars

in Zimbabwe.

VARIETY

Water

stress

toleran

ce Sadza

beer

brewing Preferences

SDU GHS Grain

yield

kg/ha

Stover

yield

kg/ha

SPV422# 2 2 2.6 4 25.1 3.3 1083 2000

SPV1411* 2 2.7 2.2 4 14.7 1.8 389 1167

PVK801* 2.4 1.3 2.4 4.5 10.2 4.3 500 778

S35# 2.1 2 2.6 3.5 14.9 2.8 311 1332

ICSR93034# 1.6 2.4 3.2 4.5 28.6 4.0 333 1056

E36-1* 2 1.7 2.4 4.5 22.8 3.0 167 500

MACIA 2 2.2 1.6 3.3 17.2 2.7 333 722

SV-4 2.8 2.5 2.8 3.3

-

-

446

889

Seredo F 1.3 2.3 1.6 2 39.6 3.4 1278 1556

Mean

LSD (5 %)

580

NS

1072

941a

CV %

30.3 29.6

Ranking was on 1-5 scale, where 1= the best, 5= the worst, a= significantly different

at 5 %, NS= not significantly different, *=male selected cultivars in previous on-

station trials, #=female selected cultivars in previous on-station trials, F= farmers

selected cultivars in on-farm trials. SDU in range of 25-35 is good for brewing, SDU >

35 very good, SDU<25 is not good for brewing. GHS = 1-2.5 soft, good for brewing,

2.6-3.4=intermediate, favourable for brewing, 3.5-5.0 = hard, good for milling and

baking quality

Farmers have problems of high bird damage which agrees with findings in Zimbabwe

where bird damage contributed to high yield loses in sorghum production (Wortman

et al., 2009). Although farmers had preferences for white sorghum grained cultivars

(Wortman et al., 2009), the majority of them are forced to grow red and brown

grained cultivar for they have minimal damage by birds and ensures household food

security. The bird resistant cultivars guarantee food security as they are able to

reach grain yields of above 900 kg/ha which is the minimum requirement for an

average household of six people per one year (Ncube et al., 2008).These bird

resistant cultivars have high levels of phenolic compounds (phenolic acids,

flavonoids, anthocyanidins and tannins) in the leaves (Ring 1984). These

compounds bind and precipitate proteins and decrease stover digestibility. Previous

studies have shown that amounts of phenolics in leaves accounts for most of the

variation in digestibility and feed intake (Reed et al., 1987). Generally bird resistant

cultivars had shown to be adequate to meet livestock maintenance requirements

only while non-bird resistant cultivars would allow weight gains when the diet is

supplemented with urea (Reed et al., 1987). However some varieties may have bird

resistant grain and low phenolic content in the crop residues.

The need for drought tolerant cultivars was also mentioned due to the high

prevalence of droughts in semi-arid environments (Hussein, 1987). The common

droughts are end of season droughts hence early maturity was also considered an

important trait among current available varieties (Table 2). The need for early

maturing cultivars is also supported by that this trait was also ranked among cultivars

in participatory variety selection and famers were able to distinguish among cultivars

on maturity (Table 5 and 6).The cultivars which were selected as superior in on-

station trials (Mativavarira et al., 2011) were not preferred under farmer’s

environments. This generally shows the need for researcher to tests cultivars under

farmers environments as this will ascertain their adoption if they perform well.

Conclusion

Our results showed the need for researchers to combined on-station and on-farm

trials on participatory variety selection. Sweet sorghum varieties have great potential

for adoption by crop-livestock farmers as long as they have important traits for food

and feed. The current sorghum breeding programmes should also focus on

development of cultivars with resistance to drought and birds. There is need for more

work to find the levels of phenolic compounds in bird resistant cultivars which

assures food and feed security for crop-livestock farmers in semi-arid areas.

Acknowledgements. We would like thank Bundesministerium fuerWirtschaftliche

Zusammenarbeit (BMZ) for funding the work. We also thank staff at Sorghum and

Millets research Unit (SMRU) of the Crop breeding institute for assisting in the data

collection and at ICRISAT –laboratory, Mr M. Madzvamuse for grain quality analysis.

References

1. Almodares, A., A. Sepahi, H. Dalilitajary and R. Gavami, (1994). Effect of

phenological stages on biomass and carbohydrate contents of sweet sorghum

cultivars Annual Plant Physiology, 8: 42-48.

2. Almodares, A., R. Taheri and V. Safavi, editors. (2008). Sorghum, Botany,

Agronomy and Biotechnology. Jahad Daneshgahi of University of Isfafan,

Isfahan

3. Central Statistics Office (1992). National Census 1992. Harare: Government

of Zimbabwe.

4. FAO (Food and Agriculture organization). 2004:

http://faostat.fao.org/faostat/notes/citation.

5. Hussein, J., (1987). Agroclimatological analysis of growing season in natural

regions III, IV and V of Zimbabwe.p25-89. In: Twomlow, S., Steyn, T. J., and

Du Preez, C, C. (2006). Dryland farming in Southern Africa. Crop science

society of agronomy (2006), 2nd ed. Agronomy Monograph no. 23.

6. Joshi, A. and Witcombe, J. R. (1996). Farmer participatory crop improvement.

II. Participatory varietal selection, a case study in India. Experimental

Agriculture 32:461–477.

7. Mativavarira, M., Dimes,J., Masikate, P., Mwenje, E., . Van Rooyen, A.,

Sikosana, J.L.N., and Hooman-Kee Tuli, S. (2011). Evaluation of water

productivity, fodder quality and farmer preferences of sweet sorghum cultivar

types in semi arid tropics of Zimbabwe. JSAT: icrisat ejournal. Icrisat.org. (in

press).

8. Mgonja, M.A., Obilana, A.B., Chisi, M., Saadan, H.M., Ipinge, S.A., Mpofu, L.,

Chintu, E., Setimela, P., Pali-Shikhulu, J., Joaquim, E., (2005). Improved

Sorghum Cultivars Released in the SADC Region. International Crops

Research Institute for Semi-Arid Tropics (ICRISAT), Bulawayo, Zimbabwe.

9. Ncube B, Twomlow SJ, Dimes JP, van Wijk MT, Giller KE. (2008). Farm

characteristics and soil fertility management strategies in smallholder farming

systems under semi-arid environments in Zimbabwe. Soil Use Manage (in

press). In: Twomlow. S., Rohrbach. D., Dimes. J., Rusike. J., Mupangwa.

W., Ncube. B., Hove. L., Moyo. M., Mashingaidze. N., Maphosa. P.,

(2010). Micro-dosing as a pathway to Africa’s Green evolution: evidence from

broad-scale on-farm trials. Nutr Cycl Agroecosyst (2010) 88:3–15.doi; 10.

1007/s10705-008-9200-4.

10. Reed, J.D., Kebede, Y., Fussell, L.K. (1987). Factors affecting the nutritive

value of sorghum and millet crop residues. In :Plant breeding and the nutritive

value of crop residues.(Reed, J.D., Capper, B.S, Neate, P.J.H.). Proceedings

of a workshop on Held at ILCA, ADDIS ABABA, ETHIOPIA, 7-10 DECEMBER

1987.

11. Ring, A.S., (1984). Total phenol and phenolic acid contents of sorghum tissue

from boot stage to post harvest –maturity weathering. M.S . Thesis, Texas

A&M University, college Station, TX.In: Doherty, C.A., Waniska, R.D.,

Rooney, L.W., Earp,C.F., and Poe, J.H. 1986. Free Phenolic Compounds and

Tannins in Sorghum caryopsis and Glumes During Development.Cereal

chem.. 64(1):42-46.

12. Tesso, T.T., L.E. Claflin and M.R. Tuinstra, (2005). Analysis of Stalk Rot

Resistance and Genetic Diversity among Drought Tolerant Sorghum

Genotypes. Crop Science, 45: 645-652. 16.

13. Twomlow, S., Steyn, T. J., and Du Preez, C, C. (2006). Dryland farming in

Southern Africa. Crop science society of agronomy (2006), 2nd Ed.

Agronomy Monograph no. 23.

14. Van-Oosteroma, E.J., P.S. Carberryb and R.C. Muchow, (2001). Critical and

minimum N contents for development and growth of grain sorghum. Field

Crop Research, 70: 55-73.

15. Vincent, V., and Thomas, R.G., (1961). An agricultural survey of Southern

Rhodesia. Part I Agro-ecological survey. Government Printer, Harare.

16. Witcombe, J. R., Joshi, A., Joshi K. D. and Sthapit, B. R. (1996). Farmer

participatory crop improvement. I. Varietal selection and breeding methods

and their impact on biodiversity. Experimental Agriculture 32:445–460.

17. Wortmann, C., Mamo, M., Mburu, C., Letayo, E., Abebe. G., Kayuki, K., Chisi,

M., Mativavarira, M. and Ndacyayisenga, T. (2009) Atlas of Sorghum

production in Eastern and Southern Africa. Intsormil.org.