Ch. 8 — The Application of Genetics to Plants • 153 
testing is needed to determine whether the impro\ement 
can he maintained in field trials, where the improved 
strains must compete against wild-Upe Rhizobia already 
present in the soil. 
Another wa\ to improve nitrogen fi.xation is to select 
plants that ha\e more efficient s\'mhiotic relationships 
with nitrogen-fi.xing organisms. Since the biological proc- 
ess retiuires a large amount of energ\' from the plant, it 
may he possible to select for plants that are more efficient 
in producing, and then to transfer the end products of 
photosynthesis to the nodules in the roots. .Also e.xisting 
nitrogen-fi.xing bacterial strains that can interact w ith crop 
plants which do not oidinarily fix nitrogen could be 
searched for or dev eloped. 
Keducing the amount of chemically fixed nitrogen 
fertilizer— and the cost of the natural gas prev iously used 
in the chemical process— would he the largest benefit of 
successfullv fixing nitrogen in crops. Knv ironmental bene- 
fits. from the smaller amount of fertilizer runoff into 
water systems, would accrue as well. But is it difficult to 
predict w hen these w ill become reality. Experts in the field 
disagree: some feel the breakthrough is imminent: others 
feel that it might take sev eral decades to achiev e. 
The refinements in breeding methods pro- 
vided bv the new technologies may allow major 
crops to be bred more and more for specialized 
uses— as feed for specific animals, perhaps, or 
to conform to special processing requirements. 
In addition, since the populations in less de\el- 
oped countries suffer more often from major 
nutritional deficiencies than those in industrial- 
ized countries, a specific export market of cere- 
al grains for human consumption, like wheat 
with higher protein levels, may be developed. 
But genetic methods are only the tools and 
catalysts for the changes in how society pro- 
duces its food; financial pressures and Federal 
regulation will continue to direct their course. 
E.g., the automation of tissue culture systems 
will decrease the labor needed to direct plant 
propagation and drastically reduce the cost per 
plantlet to a level competitive with seed prices 
for many crops. W^hile such breakthroughs may 
increase the commercial applications of many 
technologies, the effects of a displaced labor 
force and cheaper and more efficient plants are 
hard to predict. 
Although it is difficult to make economic pro- 
jections, there are several areas where genetic 
technologies w ill clearly have an impact if the 
predicted breakthroughs occur: 
• Batch culture of plant cells in automated 
systems will he enhanced by the ability to 
engineer and select strains that produce 
larger quantities of plant substances, such 
as pharmaceutical drugs. 
• The technologies will allow development of 
elite tree lines that will greatly increase 
yield, both through breeding programs 
similar to those used for agricultural crops 
and by ox ercoming breeding barriers and 
lengthy breeding cycles. Refined methods 
of selection and hybridization will increase 
the potential of short-rotation forestry, 
which can provide cellulosic substrates for 
such products as ethanol or methanol. 
• The biological efficiency of many economi- 
cally important crops wall increase. Ad- 
vances will depend on the ability of the 
techniques to select for whole plant charac- 
teristics, such as photosynthetic soil and 
nutrient efficiency.’® 
• Besides narrowing breeding goals, the 
techniques will increase the potential for 
faster improvement of underexploited 
plants with promising economic value. 
For such adxances to occur, genetic factors 
must be selected from superior germplasm, the 
genetic contributions must be integrated into 
improv'ed cultural practices, and the improved 
varieties must be efficiently propagated for 
distribution. 
’’For the soybean and tomato crops, the research area for im- 
proved biological efficiency received the highest allotment of 
funds in fiscal year 1978. Total funding was S12.9 million for soy- 
beans and S2.1 million for tomatoes. The second largest category 
to be funded was control of diseases and nematodes of soybeans at 
S5.1 million and for tomato at SI. 6 million. 
