coli, and second, with tissue cultures of specific food
and forest crops. Cell, tissue, meristem and anther
cultures provide convenient and rapid methods of
plant propagation for production of experimental
crossing lines and super disease-free plant selections.
These are the gateways through which the disciplinary
developments in genetic engineering and biotech-
nology must pass to become useful for agriculture. Im-
mediate opportunities exist for such crops as rice,
asparagus, garlic, potatoes, bananas, oil palm and
sugarcane, in the propagation of rootstocks for
deciduous fruit trees, and for rapid clonal reproduction
of many ornamentals and forest trees.
 Plant Growth Regulants A very promising area in
food research and for new technologies for the years
2000-2030 is the use of plant growth regulators. Most
that have been found occur in nature. The effects are
numerous. They range from increased yields and im-
proved quality to longer storage life for such crops as
potatoes and onions. For fruits and vegetables, matur-
ity may be hastened, fruit size increased, flower sex ex-
pression modified, senescence inhibited, and fruit and
seed production enhanced. Growth regulators are used
to aid mechanical harvesting of many fruits and
vegetables.
 Current developments attest to the importance of
DISC research in this area (Nickell, 1983). A new
generation of chemicals is now emerging that produces
shorter plants and thicker stems, and results in better
filling for heads of cereal grains with less lodging.
Using chemical ripeners on sugarcane increases the
yield of sugar by 10 percent. The content and quality
of oil in the major oil seeds and in cereals may now be
enhanced with growth regulators. With corn, growth
regulators increase yield and cause earlier pollination
and longer grain filling periods, with better tip fill,
larger leaf areas and heavier kernels. Significant yield
increases in soybeans have also been achieved. Greater
resistance to such environmental stresses as heat, cold,
drought and air pollutants have followed the use of
specific growth regulators on major food crops. Cur-
rently there are at least 40 major chemical companies
in the United States engaged in the development of
chemical growth regulators for use on major crops and
forest trees. The Plant Growth Regulator Society of
America was organized in 1980 to focus attention on
the effects of plant growth regulants on the major food
crops of the United States.
 The future role of plant growth regulators should
not be underestimated. Some compounds, such as
triacontanol, have a wide spectrum of responses on
many species of economically important plants (Ries
and Houtz, 1983). This chemical is now being pro-
duced in the People's Republic of China by over 25 in-
stitutions, which are extracting it from beeswax or


making it through direct synthesis. Sixty-seven thou-
sand hectares (165,000 acres) have thus far been
treated. Crops responding include rice, wheat, cotton,
tomato, pepper, watermelon, orange and cabbage.
Treatment consists of a concentration of 1 milligram/
liter as a spray application, repeated two or three
times. Increases in yield range from 10 to 40 percent,
with improvements in the protein content of rice and
in the sugar content of watermelon. Such results still
need to be verified, but they suggest that similar
responses for major food crops, as well as horticultural
crops, are possible.

 Greater Resistance to Competing Biological Systems
- Research in entomology and plant pathology, com-
bined with results of biochemistry research, provide a
base for improvements in technologies to protect crops
from weeds, diseases and insects.
 A matter of great concern is the mounting resistance
among pests to pesticides. There are now approxi-
mately 430 insects resistant to insecticides, 100 diseases
resistant to fungicides and bactericides, and 36 weeds
resistant to herbicides. More DISC research is needed
to determine the natures or sites of resistances, as
illustrated by Arntzen and associates (1984). The her-
bicide atrazine is used on 75 percent of the U.S. corn
acreage, but some of the most noxious weeds-lamb's-
quarters and redroot pigweed-have become resistant.
Arntzen has found that, in these instances, the site of
resistance is in the chloroplast and involves interference
with electron transport. The research that led to their
findings involved biochemists, plant physiologists,
agronomists and those in genetic engineering. DISC
research supported by public funds for pest control in
the future should likewise involve many disciplines.

 Increasing Plant Resistance to Environmental Stress
- A substantial DISC research effort aimed at improv-
ing the resistance of crops to stress caused by year-to-
year climate variations is badly needed (National
Academy of Sciences, 1976). Though potential prob-
lems of long-term climatic change-for example, from
increasing levels of atmospheric CO2-have received
considerable attention in recent years, interannual
climate variations, which have always been present,
continue to be largely ignored. Genetic, biochemical
and entomological research directed toward greater
production stability should command high priority. A
research investment in these disciplines can have a
major impact on agriculture and forestry production
and resource management by the year 2030. Improved
resistance to environmental and climatic stresses-
drought, heat, cold, problem soils, salinity and air
pollutants-can be achieved through genetic improve-
ment, chemical treatments and better management.

 Needed Relevant Disciplinary Research for Forestry