CAB129-37 — Page 382

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differences. The best yield has been produced in the neighbourhood of 50,000 plants per acre. The performance values (yield per 1,000 plants) evidently vary with population, but no detailed conclusions can be drawn from these results since the general form of the relation between plant population and performance is not known. It is evident on theoretical grounds, however, that for more or less upright varieties, where lower population is less readily compensated by greater runner growth, the relation cannot be simple.

Planting conditions

The more important results of the experiment testing a wide range of variables in mechanical planting conditions and technique referred to on page 113 appear in Table 20. Planting was very late, on 13th and 26th March, and the experi- ment was not intended to provide more than germination data.

Table 20.-Results of Experiment on Planting Variables, Groundnuts, Kongwa Experiment Station, 1947-48

Percentage establishment of seed theoretically planted

200

Depth

Machine Hand

Natal Common

Valencia!

Mean

2"

4"

Dry period after planting 14 Wet period after planting

25

26

13

18

49

44

44

•

49

53

20

20

19

40

46

Mean

31

34

55

31

36

30

33

Date of planting

An experiment was set out at Kongwa Experimental Station to test the effect on yield of five different varieties of varying dates of planting. The planting dates were December 24, and January 2, 14 and 28.

The varieties tested were the short season bunch types, Spanish Bunch and Natal Common, the short season semi-bunch Valencia, the long season semi- bunch Virginia Bunch, and the local long season variety Kongwa, which is in fact a mixture of strains of varying growth habit, mostly runner, but with an upright component.

The full results were as follows:-

B

Table 21.-Results of Date of Planting Experiment, Groundnuts, Kongwa Experiment Station, 1947-48

Date of Planting

Valencia Spanish

Natal Virginia Common Bunch

Kongwa

Mean

I. Plant population,

000/acre:

December 24 January

January January 28

2242243

Mean

7-7

23.7

24.0

24.2

18.7

19.7

24.2

23.9

...

20.9

21.7

18.2

21.8

14

·14.5

21.7

23.4

22.4

17.5

19.9

25.9

8.7

18.1

. 15.1

17.2

17.0

18.1

19-5

21.6

20.9

17.9

19.6

II. Yields, lbs. (±67·8 for vertical comparisons only, ±79.7 for others) (±30·4)

I

kernels/acre:

December 24

557

1,289

1,189

1,636

1,486

1,231

January 2

1,096

1,268

1.064

1,236

1,039

1,141

January 14

696

900

1,028

693

628

789

January 28

793

321

550

375

464

501

Mean (+26.9)

786

945

958

985

904

916

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