dominant characters from both parents plus any recessive characters present in both parents that may come 
together to form a homozygous genotype, in which case such recessive characters would be expressed in the Fi 
generation cross. 
Inbreeding of the Fi generation cross will cause the phenotypes to break down into homozygous dominant 
characters, homozygous recessive characters and heterozygous characters: the ratio being 25 per cent homozygous 
dominant, 25 per cent homozygous recessive. These will breed true as such in all future generations if main¬ 
tained in the homozygous condition. 50 per cent of the population will be heterozygous and phenotypically will 
be like the homozygous dominant but genotypically will be like the Fi generation cross and will break down in 
similar ratios when inbred. The eventual result is that a new variety is developed which may combine the de¬ 
sirable characteristics of both parents by careful selection and inbreeding over a number of generations. It 
usually requires at least three generations of this work and often many more to produce a fixed type. Sometimes 
it becomes necessary to back cross to either one or the other or both of the parents to establish some particular 
characteristic which may be desired. The field of hybridization offers some possibilities toward higher accomplish¬ 
ments among vine seed. So far no one seems to have conducted sufficient experiments to exhaust the results 
that may be expected. 
Some success has been recorded in the use of pickling blends in cucumber seed. It usually consists of a 
mechanical mixture of seed of three varieties. This includes about 80 per cent of the most desirable kind with 
10 per cent each of two similar varieties. It is believed that a certain amount of hybridization exists which may 
tend to increase yields and perhaps include other advantages to a limited degree at least. In our opinion it pri¬ 
marily serves to produce an assortment of types which may be desirable for the various sizes required for packing. 
The fact that these individual varieties are not pure line strains would prevent a result which could be definitely 
determined in advance, so far as type is concerned, by cross-pollination. Usually it is not advisable that seed 
from these blends be used for reproduction because individual types would eventually disappear by the crossing 
of varieties. 
METAXENIA 
There apparently is no metaxenia among Cucurbits; that is, no instant effect of the pollen in hybridization 
on the fruits themselves, so far as can be determined by the naked eye, although it may be possible that pollen 
from an unrelated plant may have a somewhat more invigorating effect and thus increase yields to some extent. 
It seems apparent that this has been demonstrated under growing conditions when two stocks have accidently 
crossed. There appears to have been an increase in the yield of fruits; however, no effect is noticeable that 
would indicate crossing between the two varieties in the first season and it would not actually be discovered un¬ 
til the following generation. 
ISOLATION 
The distance between varieties to avoid mixture is an open question. It is safe to believe that pollen can 
be carried as far as bees can fly or as long as the pollen retains its reproductive characteristics. Likely no harm¬ 
ful quantity would be carried over long distances at any one time but when two crops are produced within a 
close distance of each other, a considerable mixture may be expected among those crops which will readily cross- 
pollinate. 
In our tests we have not found that any of the Cucurbits will cross outside of their own genus. In the case 
of Squash and Pumpkin, which are divided into different groups but of the same family, the two groups, C. 
Maxima and C. Moschata will cross. Likewise C. Moschata and C. Pepo will cross. Otherwise no other combi¬ 
nations in vine seed will habitually cross-pollinate under ordinary conditions; however, any two varieties of the 
same genus will naturally cross, readily, within the distance that pollen may be disseminated by insects. 
There is no truth to the ancient belief that cucumber affects the flavor or quality of muskmelon when plant¬ 
ed close together. In our experiments of hand pollination between staminate blossoms of cucumber on pistillate 
blossoms of muskmelon, fertilization did not occur. On very rare occassions the fruit would continue to enlarge 
for a time, but in no instance did it reach maturity. From the results reported by others in this same experiment, 
a fruit has attained almost full size and was nonnal in appearance but seed did not develop and reproduction 
would thus be impossible. This therefore goes to prove that when mixtures or off-types occur in vine seed they 
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