In field and greenhouse studies, more cereal leaf beetle [Oulema melanopus (Lin- naeus)] eggs and larvae were found per unit area on spring oats, Avena sativa L., planted either at intermediate (54 kg/ha) or high (136 kg/ha) seeding rates, than when planted at a lower seeding rate (14 kg/ha). However, there were fewer eggs and larvae per stem in plantings of the high or intermediate rates than in those of the lower rate. Oats should not be planted at less than the recommended rates in beetle-infested areas

Gage, S. H

Smith, D. H

Webster, J. A

English

Valparaiso University

The Great Lakes Entomologist Volume 11 Number 2 - Summer 1978 Number 2 - Summer 1978 Article 7 June 1978 Cereal Leaf Beetle (Coleoptera: Chrysomelidae) Influence of Seeding Rate of Oats on Populations J. A. Webster Michigan State University D. H. Smith Michigan State University S. H. Gage Michigan State University Follow this and additional works at: https://scholar.valpo.edu/tgle  Part of the Entomology Commons Recommended Citation Webster, J. A.; Smith, D. H.; and Gage, S. H. 1978. "Cereal Leaf Beetle (Coleoptera: Chrysomelidae) Influence of Seeding Rate of Oats on Populations," The Great Lakes Entomologist, vol 11 (2) Available at: https://scholar.valpo.edu/tgle/vol11/iss2/7 This Peer-Review Article is brought to you for free and open access by the Department of Biology at ValpoScholar. It has been accepted for inclusion in The Great Lakes Entomologist by an authorized administrator of ValpoScholar. For more information, please contact a ValpoScholar staff member at scholar@valpo.edu. 1978 THE GREAT LAKES ENTOMOLOGIST CEREAL LEAF BEETLE (COLEOPTERA: CHRYSOMELIDAE): INFLUENCE OF SEEDING RATE OF OATS ON POPULATIONS~ J. A. ~ e b s t e r , ~  D. H. Smith, J I . , ~  and S. H.  age^ ABSTRACT In field and greenhouse studies, more cereal leaf beetle [Oulema melanopus (Lin- naeus)] eggs and larvae were found per unit area on spring oats, Avena sativa L., planted either at intermediate (54 kg/ha) or high (136 kg/ha) seeding rates, than when planted at a lower seeding rate (14 kg/ha). However, there were fewer eggs and larvae per stem in plantings of the high or intermediate rates than in those of the lower rate. Oats should not be planted at less than the recommended rates in beetle-infested areas. Since the detection of the cereal leaf beetle (CLB), Oulema melanopus (Linnaeus), in North America, a variety of pest management efforts have been made, including quarantine, chemical and biological control, plant resistance, and various cultural prac- tices. One cultural practice that has been shown to reduce the population densities of other insect pests of small grains is seeding rate. For example, Luginbill and McNeal (1958) found that infestation and cutting of wheat by the wheat stem sawfly, Cephus cirrctus Norton, decreased as the seeding rate increased and row spacing decreased. Apparently, the sawfly selected the larger, more succulent stems in the plots with fewer stems per unit area Also, Agrios (1969) reported that better yields of barley were sometimes obtained despite the presence of barley yellow dwarf by increasing the number of plants per unit area through increased planting rates. When there were few aphid vectors, a greater number of plants escaped infection, but when the density of aphids was great, healthy plants could not be found in most fields, regardless of seeding rate. In parts of Russia, dense sowings in spring wheat nurseries are often used to reduce damage from a frit fly, Oscinosoma pusilla Meigen (Maistrenko, 1976). Recommended rates, however, may not be used in planting for various reasons ranging from limited seed supplies to an improperly calibrated grain drill. Grafius (1956) and Woodward (1956) both found that in the absence of insects, diseases, or other stresses, wide variations in seeding rates of oats (around the optimum) produced only minor variations in yield. Woodward (1956) stated that on western irrigated land, farmers who planted at half the usual rate could afford to plant certified seed at no extra cost, and could thus reduce many farm problems associated with plant diseases and grain mixtures. The present work is the initial phase of a long-term study to determine whether seeding rate can be used as a cultural practice in CLB management. In this work, we report the influence of three seeding rates of spring oats in small plots and in the greenhouse on CLB populations. MATERIALS AND METHODS Clintland 64 (C.I. 7639) oats were sown at rates of 14, 54, and 136 kg/ha [the recommended seeding rate in Michigan is 72-90 kg/ha (Hildebra5d and Copeland, 1975)l l ~ i c h i ~ a n  Agricultural Experiment Station Journal Article 8033. Part of a cooperative project between the Agricultural Research Service, USDA, and the Entomology Depart- ment and Crop and Soil Sciences Department, Michigan State University, East Lansing, MI 48824. 2~esearch Entomologist, USDA, Agricultural Research Service, Department of En- tomology, Michigan State University, East Lansing, MI 48824. 3~esearch Geneticist, USDA, Agricultural Research Service, Department of Crop and Soil Sciences, Michigan State University, East Lansing, MI 48824. 4~epar tment  of Entomology, Michigan State University, East Lansing, MI 48824. 1Webster et al.: Cereal Leaf Beetle (Coleoptera: Chrysomelidae) Influence of SeediPublished by ValpoScholar, 1978118 THE GREAT LAKES ENTOMOLOGIST Vol. 11, No. 2 in 1970 and 1971. A 3 x 3 Latin square design with 6 X 6 m plots was used in 1970, while 9 X 27 m randomized strips with 1 striplseeding rate were used in 1971. Plantings were made at two Michigan locations in 1970: Ingham County (1 May) and Kalamazoo County (5 May). In 1971, plots were sown in Kalamazoo County on 4 May. In 1970, estimates of plant density were obtained by counting the number of stems collected on 19 June from 6 1 cm of row. In 1971, stem counts were made periodically, and also from 61 cm of row, but without removing the plant material from the field. In 1970, one estimate of the CLB population was made by counting eggs and larvae on the 19 June plant samples. In 1971, cumulative egg input (Helgesen and Haynes, 1972) was used as an insect population Index. Counts were made at 3 4  day intervals in the same 61 cm sections of row during the oviposition period in late May and early June. At each sampling, the eggs found and counted were destroyed so none remained on the plants. Counts within the survey row were totaled at the end of the oviposition season to obtain the cumulative egg input. Since 1971 the CLB population densities have not been great enough at  the test sites to obtain suitable data on the interaction of the CLB and plant density; therefore, a similar experiment was conducted in the greenhouse. Oats were planted and thinned in two rows, 17.8 cm apart, in soil in standard wood flats to obtain about the same plant densities as in the field tests. One flat of each seeding density was randomly positioned in each of four s'creened oviposition cages. Each cage was held in a greenhouse with conditions similar to those described by Schillinger (1969). When the seedlings were in the early two-leaf stage, ca. 15 cm high, 100 field-collected spring adult CLB were introduced into each cage. Egg counts/30.5 cm of row were made 72 hours later. RESULTS AND DISCUSSlON Figure 1 and Table 1 show that CLB counts per unit area were directly related to the number of oat stems per unit area when CLB populations were high, as in 1971. Also, there was an inverse relationship between oat stems per unit area and CLB counts per stem, but this relationship was only clearly evident in the greenhouse test (egg counts) and to a lesser extent in the 1970 Kellogg test (egg and larval counts) (Table 2). When populations were much lower (30 eggs161 cm of row in tests not reported here), linear relationships between stem density and CLB eggs per unit area or e s s  per stem were not evident. Several environmental factors need to be considered to interpret the data obtained in this study. For example, the CLB adult developmental temperature threshold is 9.9"C (Gage, 1972), while that of oats is between 3.3"C and 4.4"C (Coffman, 1923; W i ~ a n s ,  1956). Thus, in cool growing seasons, oat plants in thinly seeded fields may compensate by producing tillers so that by peak beetle activity, differences in tiller numlxrs lxtween plots planted at  different seeding rates will be minor. But lxcause of wet soil conditions in the spring, the Michigan oat crop is often planted late enough so that peak beetle activity occurs in the early seedling stage. When this occurs, our hypothesis is that there will be greater beetle pressure per plant accompanied by reduced grain yield and quality. Unfortunately, our insect and grain yield data from more recent unpublished tests (which included plots seeded at  the recommended planting rates) have not been suitable to test the interaction of the beetle with the ga in  because of low populations. Several years of yield data including the effect on panicles per unit area, 1000 kernel weight, kernels per panicle, and leaf feeding damage are needed to completely understand the relationship of planting rates and the CLB. Until more yield data can be obtained, we believe that planting oats at less than recommended rates, while economically feasible in some parts of the country, is not a sound practice in CLB-infested areas. LITERATURE CITED Agrios, G. N. 1969. Plant pathology. Academic Press, New York. Coffman, F. A. 1923. The minimum temperature of germination of seeds. J. Amer. Soc. Agron. 15:257-270. 2The Great Lakes Entomologist, Vol. 11, No. 2 [1978], Art. 7https://scholar.valpo.edu/tgle/vol11/iss2/7THE GREAT LAKES ENTOMOLOGIST Fig. 1. Relationship between oat stems per unit area and CLB eggs per unit area when seedling oats were infested with dense populations of spring adult CLBs. 0 Q - dO N- d 0 0 - x - 0 E L L  0 0 - E m U - (D \ % g- c9 W m -1 O-  * 0-  01 0 0 Table,]. Cereal leaf beetle counts per unit area on Clintland 64 oats seeded at three rates. 1970, n = 9; 1971, 1975, n = 4. MAY 2 0 ,  1971 CI CI I I I I I I I 20 40 60 80 100 120 140 CLB counts 2 SEa on oats seeded at indicated rates OAT S T E N S / 6 1  CM OF ROW Year an t  location Lowest Intermediate Highest L S D ~ . ~ 5 c  - - a1970: Combined egg and larva1 counts from 61 cm of row on 19 June. 1971: Cumulative eggs per 61 cm of row during the oviposition period. 1975: Cumulative eggs per 30.5 cm of row 3 days after infestation. b~ = Kalamazoo County, MI; I = Ingham County, MI; G = greenhouse. V o r  mean separation horizontally; ns = horizontal means ndt significantly different. 3Webster et al.: Cereal Leaf Beetle (Coleoptera: Chrysomelidae) Influence of SeediPublished by ValpoScholar, 1978120 THE GREAT LAKES ENTOMOLOGIST Vol. 11, No. 2 Table 2. Cereal leaf beetle counts per oat stem on Clintland 64 oats seeded at three rates. The stem density for the corresponding date is shown in parenthesesa. 1970, n = 9; 1971, n = 4 .  CLB counts/stem i S E ~  on oats seeded at indicated rates Year location and datec Lowest Intermediate Highest L S D ~ . ~ 5 d  1970-K 19 June 0.8 + 0.1 (21.7 * 1.8) 1970-1 0.5 + 0.1 (15.7 + 1.7) 197 1-K 20 May 1.5 + 0.3 (14.5 * 1.7) 1975-G 8 May 6.4 + 1.3 (8.0) aStems/61 cm-field, stems/30.5 cm-greenhouse. b ~ a t i o  f CLB counts per unit area to stems per unit area. Combined egg and larval counts in 1970, egg counts in, 1971 and 1975. CK = Kalamazoo County, MI; I = Ingham County, MI; G = greenhouse. d ~ o r  mean separation horizontally; ns = horizontal means not significantly different. Gage, S. H. 1972. The cereal leaf beetle, Oulema melanopus and its interaction with two primary hosts: Winter wheat and spring oats. PhD. Thesis, Mich. State Univ. Grafius, J. E. 1956. The relationship of stand to panicles per plant and per unit area in oats. Agron. J. 48:56-59. Helgesen, R. G. and D. L. Haynes. 1972. Population dynamics of the cereal leaf beetle, Oulem melanopus (L.): a model for age specific mortality. Can. Entomol. 104:797-814. Hildebrand, S. C. and L. 0. Copeland. 1975. Seeding practices for Michigan crops. Mich. State Univ. Coop. Ext. Serv. Ext. Bull. E-489. Luginbill, P., Jr. and F. H. McNeal. 1958. Influence of seeding density and row spacings on the resistance of spring wheats to the wheat stem sawfly. J. Econ. Entomol. 5 1: 804-808. Maistrenko, 0. I. 1976. Identification and localization of the genes controlling leaf pubescence in young plants of wheat. Genetika 12:5-15. Schillinger, J. A. 1969. Three laboratory techniques for screening small grains for resistance to the cereal leaf beetle. J. Econ. Entomol. 62:360-363. Wiggins, S. C. 1956. The effect of seasonal temperatures on maturity of oats planted at different dates. Agron. J. 48:21-25. Woodward, R. W. 1956. The effect of rate and date of seeding of small grains on yields. Agron. J. 48: 160-162. 4The Great Lakes Entomologist, Vol. 11, No. 2 [1978], Art. 7https://scholar.valpo.edu/tgle/vol11/iss2/7

Cereal Leaf Beetle (Coleoptera: Chrysomelidae) Influence of Seeding Rate of Oats on Populations

ValpoScholar

The Great Lakes Entomologist 
Volume 11 
Number 2 - Summer 1978 Number 2 - Summer 
1978 
Article 7 
June 1978 
Cereal Leaf Beetle (Coleoptera: Chrysomelidae) Influence of 
Seeding Rate of Oats on Populations 
J. A. Webster 
Michigan State University 
D. H. Smith 
Michigan State University 
S. H. Gage 
Michigan State University 
Follow this and additional works at: https://scholar.valpo.edu/tgle 
 Part of the Entomology Commons 
Recommended Citation 
Webster, J. A.; Smith, D. H.; and Gage, S. H. 1978. "Cereal Leaf Beetle (Coleoptera: Chrysomelidae) 
Influence of Seeding Rate of Oats on Populations," The Great Lakes Entomologist, vol 11 (2) 
Available at: https://scholar.valpo.edu/tgle/vol11/iss2/7 
This Peer-Review Article is brought to you for free and open access by the Department of Biology at ValpoScholar. 
It has been accepted for inclusion in The Great Lakes Entomologist by an authorized administrator of ValpoScholar. 
For more information, please contact a ValpoScholar staff member at scholar@valpo.edu. 
1978 THE GREAT LAKES ENTOMOLOGIST 
CEREAL LEAF BEETLE (COLEOPTERA: CHRYSOMELIDAE): 
INFLUENCE OF SEEDING RATE OF OATS ON POPULATIONS~ 
J. A. ~ e b s t e r , ~  D. H. Smith, J I . , ~  and S. H.  age^ 
ABSTRACT 
In field and greenhouse studies, more cereal leaf beetle [Oulema melanopus (Lin- 
naeus)] eggs and larvae were found per unit area on spring oats, Avena sativa L., planted 
either at intermediate (54 kg/ha) or high (136 kg/ha) seeding rates, than when planted at 
a lower seeding rate (14 kg/ha). However, there were fewer eggs and larvae per stem in 
plantings of the high or intermediate rates than in those of the lower rate. Oats should 
not be planted at less than the recommended rates in beetle-infested areas. 
Since the detection of the cereal leaf beetle (CLB), Oulema melanopus (Linnaeus), in 
North America, a variety of pest management efforts have been made, including 
quarantine, chemical and biological control, plant resistance, and various cultural prac- 
tices. One cultural practice that has been shown to reduce the population densities of 
other insect pests of small grains is seeding rate. For example, Luginbill and McNeal 
(1958) found that infestation and cutting of wheat by the wheat stem sawfly, Cephus 
cirrctus Norton, decreased as the seeding rate increased and row spacing decreased. 
Apparently, the sawfly selected the larger, more succulent stems in the plots with fewer 
stems per unit area Also, Agrios (1969) reported that better yields of barley were 
sometimes obtained despite the presence of barley yellow dwarf by increasing the number 
of plants per unit area through increased planting rates. When there were few aphid 
vectors, a greater number of plants escaped infection, but when the density of aphids was 
great, healthy plants could not be found in most fields, regardless of seeding rate. In 
parts of Russia, dense sowings in spring wheat nurseries are often used to reduce damage 
from a frit fly, Oscinosoma pusilla Meigen (Maistrenko, 1976). 
Recommended rates, however, may not be used in planting for various reasons ranging 
from limited seed supplies to an improperly calibrated grain drill. Grafius (1956) and 
Woodward (1956) both found that in the absence of insects, diseases, or other stresses, 
wide variations in seeding rates of oats (around the optimum) produced only minor 
variations in yield. Woodward (1956) stated that on western irrigated land, farmers who 
planted at half the usual rate could afford to plant certified seed at no extra cost, and 
could thus reduce many farm problems associated with plant diseases and grain mixtures. 
The present work is the initial phase of a long-term study to determine whether 
seeding rate can be used as a cultural practice in CLB management. In this work, we 
report the influence of three seeding rates of spring oats in small plots and in the 
greenhouse on CLB populations. 
MATERIALS AND METHODS 
Clintland 64 (C.I. 7639) oats were sown at rates of 14, 54, and 136 kg/ha [the 
recommended seeding rate in Michigan is 72-90 kg/ha (Hildebra5d and Copeland, 1975)l 
l ~ i c h i ~ a n  Agricultural Experiment Station Journal Article 8033. Part of a cooperative 
project between the Agricultural Research Service, USDA, and the Entomology Depart- 
ment and Crop and Soil Sciences Department, Michigan State University, East Lansing, 
MI 48824. 
2~esearch Entomologist, USDA, Agricultural Research Service, Department of En- 
tomology, Michigan State University, East Lansing, MI 48824. 
3~esearch Geneticist, USDA, Agricultural Research Service, Department of Crop and 
Soil Sciences, Michigan State University, East Lansing, MI 48824. 
4~epar tment  of Entomology, Michigan State University, East Lansing, MI 48824. 
1
Webster et al.: Cereal Leaf Beetle (Coleoptera: Chrysomelidae) Influence of Seedi
Published by ValpoScholar, 1978
118 THE GREAT LAKES ENTOMOLOGIST Vol. 11, No. 2 
in 1970 and 1971. A 3 x 3 Latin square design with 6 X 6 m plots was used in 1970, 
while 9 X 27 m randomized strips with 1 striplseeding rate were used in 1971. Plantings 
were made at two Michigan locations in 1970: Ingham County (1 May) and Kalamazoo 
County (5 May). In 1971, plots were sown in Kalamazoo County on 4 May. 
In 1970, estimates of plant density were obtained by counting the number of stems 
collected on 19 June from 6 1 cm of row. In 1971, stem counts were made periodically, 
and also from 61 cm of row, but without removing the plant material from the field. 
In 1970, one estimate of the CLB population was made by counting eggs and larvae 
on the 19 June plant samples. In 1971, cumulative egg input (Helgesen and Haynes, 
1972) was used as an insect population Index. Counts were made at 3 4  day intervals in 
the same 61 cm sections of row during the oviposition period in late May and early June. 
At each sampling, the eggs found and counted were destroyed so none remained on the 
plants. Counts within the survey row were totaled at the end of the oviposition season to 
obtain the cumulative egg input. 
Since 1971 the CLB population densities have not been great enough at  the test sites 
to obtain suitable data on the interaction of the CLB and plant density; therefore, a 
similar experiment was conducted in the greenhouse. Oats were planted and thinned in 
two rows, 17.8 cm apart, in soil in standard wood flats to obtain about the same plant 
densities as in the field tests. One flat of each seeding density was randomly positioned in 
each of four s'creened oviposition cages. Each cage was held in a greenhouse with 
conditions similar to those described by Schillinger (1969). When the seedlings were in 
the early two-leaf stage, ca. 15 cm high, 100 field-collected spring adult CLB were 
introduced into each cage. Egg counts/30.5 cm of row were made 72 hours later. 
RESULTS AND DISCUSSlON 
Figure 1 and Table 1 show that CLB counts per unit area were directly related to the 
number of oat stems per unit area when CLB populations were high, as in 1971. Also, 
there was an inverse relationship between oat stems per unit area and CLB counts per 
stem, but this relationship was only clearly evident in the greenhouse test (egg counts) 
and to a lesser extent in the 1970 Kellogg test (egg and larval counts) (Table 2). When 
populations were much lower (30 eggs161 cm of row in tests not reported here), linear 
relationships between stem density and CLB eggs per unit area or e s s  per stem were not 
evident. 
Several environmental factors need to be considered to interpret the data obtained in 
this study. For example, the CLB adult developmental temperature threshold is 9.9"C 
(Gage, 1972), while that of oats is between 3.3"C and 4.4"C (Coffman, 1923; W i ~ a n s ,  
1956). Thus, in cool growing seasons, oat plants in thinly seeded fields may compensate 
by producing tillers so that by peak beetle activity, differences in tiller numlxrs lxtween 
plots planted at  different seeding rates will be minor. But lxcause of wet soil conditions 
in the spring, the Michigan oat crop is often planted late enough so that peak beetle 
activity occurs in the early seedling stage. When this occurs, our hypothesis is that there 
will be greater beetle pressure per plant accompanied by reduced grain yield and quality. 
Unfortunately, our insect and grain yield data from more recent unpublished tests 
(which included plots seeded at  the recommended planting rates) have not been suitable 
to test the interaction of the beetle with the ga in  because of low populations. Several 
years of yield data including the effect on panicles per unit area, 1000 kernel weight, 
kernels per panicle, and leaf feeding damage are needed to completely understand the 
relationship of planting rates and the CLB. Until more yield data can be obtained, we 
believe that planting oats at less than recommended rates, while economically feasible in 
some parts of the country, is not a sound practice in CLB-infested areas. 
LITERATURE CITED 
Agrios, G. N. 1969. Plant pathology. Academic Press, New York. 
Coffman, F. A. 1923. The minimum temperature of germination of seeds. J. Amer. Soc. 
Agron. 15:257-270. 
2
The Great Lakes Entomologist, Vol. 11, No. 2 [1978], Art. 7
https://scholar.valpo.edu/tgle/vol11/iss2/7
THE GREAT LAKES ENTOMOLOGIST 
Fig. 1. Relationship between oat stems per unit area and CLB eggs per unit area when 
seedling oats were infested with dense populations of spring adult CLBs. 
0 Q - d
O N- d 
0 
0 - 
x - 
0 
E 
L L  
0 
0 - 
E m 
U 
- 
(D 
\ 
% g- 
c9 
W 
m 
-1 
O-  * 
0-  
01 
0 
0 
Table,]. Cereal leaf beetle counts per unit area on Clintland 64 oats seeded at three rates. 
1970, n = 9; 1971, 1975, n = 4. 
MAY 2 0 ,  1971 
CI 
CI 
I I I I I I I 
20 40 60 80 100 120 140 
CLB counts 2 SEa on oats 
seeded at indicated rates 
OAT S T E N S / 6 1  CM OF ROW 
Year an t  
location Lowest Intermediate Highest L S D ~ . ~ 5 c  
- - 
a1970: 
Combined egg and larva1 counts from 61 cm of row on 19 June. 1971: Cumulative 
eggs per 61 cm of row during the oviposition period. 1975: Cumulative eggs per 30.5 cm 
of row 3 days after infestation. 
b~ = Kalamazoo County, MI; I = Ingham County, MI; G = greenhouse. 
V o r  mean separation horizontally; ns = horizontal means ndt significantly different. 
3
Webster et al.: Cereal Leaf Beetle (Coleoptera: Chrysomelidae) Influence of Seedi
Published by ValpoScholar, 1978
120 THE GREAT LAKES ENTOMOLOGIST Vol. 11, No. 2 
Table 2. Cereal leaf beetle counts per oat stem on Clintland 64 oats seeded at three rates. 
The stem density for the corresponding date is shown in parenthesesa. 1970, n = 9; 1971, 
n = 4 .  
CLB counts/stem i S E ~  on oats 
seeded at indicated rates 
Year 
location 
and datec Lowest Intermediate Highest L S D ~ . ~ 5 d  
1970-K 
19 June 0.8 + 0.1 
(21.7 * 1.8) 
1970-1 0.5 + 0.1 
(15.7 + 1.7) 
197 1-K 
20 May 1.5 + 0.3 
(14.5 * 1.7) 
1975-G 
8 May 6.4 + 1.3 
(8.0) 
aStems/61 cm-field, stems/30.5 cm-greenhouse. 
b ~ a t i o  f CLB counts per unit area to stems per unit area. Combined egg and larval counts 
in 1970, egg counts in, 1971 and 1975. 
CK = Kalamazoo County, MI; I = Ingham County, MI; G = greenhouse. 
d ~ o r  mean separation horizontally; ns = horizontal means not significantly different. 
Gage, S. H. 1972. The cereal leaf beetle, Oulema melanopus and its interaction with two 
primary hosts: Winter wheat and spring oats. PhD. Thesis, Mich. State Univ. 
Grafius, J. E. 1956. The relationship of stand to panicles per plant and per unit area in 
oats. Agron. J. 48:56-59. 
Helgesen, R. G. and D. L. Haynes. 1972. Population dynamics of the cereal leaf beetle, 
Oulem melanopus (L.): a model for age specific mortality. Can. Entomol. 
104:797-814. 
Hildebrand, S. C. and L. 0. Copeland. 1975. Seeding practices for Michigan crops. Mich. 
State Univ. Coop. Ext. Serv. Ext. Bull. E-489. 
Luginbill, P., Jr. and F. H. McNeal. 1958. Influence of seeding density and row spacings 
on the resistance of spring wheats to the wheat stem sawfly. J. Econ. Entomol. 
5 1: 804-808. 
Maistrenko, 0. I. 1976. Identification and localization of the genes controlling leaf 
pubescence in young plants of wheat. Genetika 12:5-15. 
Schillinger, J. A. 1969. Three laboratory techniques for screening small grains for 
resistance to the cereal leaf beetle. J. Econ. Entomol. 62:360-363. 
Wiggins, S. C. 1956. The effect of seasonal temperatures on maturity of oats planted at 
different dates. Agron. J. 48:21-25. 
Woodward, R. W. 1956. The effect of rate and date of seeding of small grains on yields. 
Agron. J. 48: 160-162. 
4
The Great Lakes Entomologist, Vol. 11, No. 2 [1978], Art. 7
https://scholar.valpo.edu/tgle/vol11/iss2/7


https://scholar.valpo.edu/cgi/viewcontent.cgi?article=1330&context=tgle

Cereal Leaf Beetle (Coleoptera: Chrysomelidae) Influence of Seeding Rate of Oats on Populations

Abstract

Similar works

Full text

Available Versions

Valparaiso University

ValpoScholar