CHANGE IN PROPORTION OF PEA FOLIAGE TYPES AFTER ONE SEASON OF GROWTH AS A MIXTURE

RESEARCH REPORTS

PNL Volume 12

1980

CHANGE IN PROPORTION OF PEA FOLIAGE TYPES AFTER ONE SEASON OF GROWTH AS A

MIXTURE

Wehner, T. C. and

E. T. Gritton

North Carolina State University, Raleigh, NC USA

University of Wisconsin, Madison, WI USA

Some mixtures of pea foliage types are superior to the normal type for

a number of important agronomic characteristics (Wehner, T.C. PhD thesis,

University of Wisconsin, Madison, WI. 83 p. 1979). Our objective in this

study was to determine whether these mixtures of foliage types changed

significantly from the original 1:1 composition after one season of growth.

Four foliage types near-isogenic for the genes af, t1, and st were

developed in each of seven genetic backgrounds. The four foliage types were

afaf T1T1 StSt (afila) where the leaflets are replaced by extra tendrils,

AfAf tltl StSt ( acacia) where the tendrils are replaced by extra leaflets,

AfAf T1T1 stst (reduced stipule) where the stipules are reduced to small

strap-shaped structures, and AfAf tltlstst where there are both extra leaflets

and reduced stipules. These foliage types will be referred to using only

the gene(s) in homozygous recessive condition—af, tl, st, and sttl. The

seven lines used were 'Alsweet', 'Sprite', 'New Season', 'New Line Early

Perfection' (NLEP), 'Dark Skin Perfection' (DSP), and two experimentals,

Line-1 and Line-2, from G. A. Marx, Geneva, New York. Three mixtures were

tested—af+st, af+sttl, and tl+st—and were produced by mixing equal

weights of seed^-of the two foliage types. Plots were grown at Arlington,

Wisconsin, in 1977 as part of a larger experiment. Dry seed harvested from

each mixture was planted in 1978 in low density rows, and each foliage type

was counted. Data were compared to the 1:1 expected ratio using Chi-square

analysis.

Of the three foliage type mixtures, only af+sttl remained unchanged

from the original 1:1 composition (Table 1.) The af foliage type increased

to 53.6% of the af+st mixture, and the tl type increased to 62.9% [63.1?-Ed.]

of the tl+st mixture. The exceptions to this were that the foliage type

mixtures in the cultivars Sprite and New Season remained unchanged in

composition after one season of growth. We concluded that it would be

necessary to remake the foliage type mixtures each year for the af+st and

tl+st mixtures but not for af+sttl.